+---
+title: Chillers
+category: Mechanical
+toc_depth: 3
+description: >
+ When to use: Packaged factory-assembled water-cooled and air-cooled liquid chillers for commercial, institutional, and industrial HVAC service. Covers centrifugal, screw, and scroll compressor machines from approximately 50 tons through 3,000 tons producing chilled water for comfort cooling and process cooling within the standard HVAC temperature range (typically 38°F to 55°F leaving chilled water). Includes the chiller package — compressor(s), evaporator, condenser (water-cooled shell-and-tube or air-cooled finned-coil with integral condenser fans), refrigerant circuit, oil management, microprocessor unit controller, integral power and control panel, and factory-mounted accessories. Both fixed-speed and variable-speed compressor drives are addressed.
+
+ Not intended for: Absorption chillers (driven by steam, hot water, or direct-fired heat input rather than electric compressor); air-cooled refrigerant condensing units paired with field-installed evaporators; DX rooftop and split-system equipment with refrigerant evaporators ([[syncs/rooftop-packaged-units]] where present); process chillers for industrial cooling at non-HVAC temperatures; low-temperature glycol industrial chillers below approximately 20°F leaving fluid temperature; modular skid-mounted chillers assembled in the field from separate components; and water-source heat pumps. The condenser water system, chilled water distribution piping, and cooling tower are covered separately — see [[syncs/hvac-pumps]], [[syncs/hydronic-piping]], and the cooling tower standard. Variable frequency drives external to the chiller package (where a starter is field-furnished) are covered in [[syncs/hvac-variable-frequency-drives]].
+---
+
+# Scope
+
+This specification covers packaged factory-assembled liquid chillers using vapor-compression refrigeration to produce chilled water for HVAC service. Equipment covered includes the complete chiller package as shipped from the manufacturer: compressor(s) with drive, evaporator (cooler), condenser, refrigerant circuit and charge, lubrication system, microprocessor unit controller, integral power and control enclosure, factory-mounted starter or variable frequency drive where applicable, and the integral accessories listed under Accessories & Options. Both water-cooled chillers (using a separate condenser water loop served by a cooling tower or other heat rejection source) and air-cooled chillers (rejecting heat directly to ambient air through integral condenser fans) are addressed.
+
+A chiller is a single integrated machine but it sits at the center of a system. Its performance, reliability, and service life depend as much on the design and condition of the systems connected to it — the condenser water loop, the chilled water distribution, the electrical service, and the building automation system — as on the machine itself. The Contractor shall coordinate chiller installation with [[syncs/hvac-pumps]] for chilled water and condenser water pumps, [[syncs/hydronic-piping]] for piping sizing and arrangement at the chiller connections, [[syncs/hvac-water-treatment]] for both closed-loop chilled water chemistry and open-loop condenser water chemistry and Legionella risk management, [[syncs/building-automation-system]] for control integration, [[syncs/testing-adjusting-and-balancing]] for system flow verification, [[syncs/concrete-pads]] for the housekeeping pad, [[syncs/grounding-and-bonding]] for equipment grounding, and [[syncs/equipment-labeling]] for nameplate and arc-flash labeling.
+
+The boundary of work under this standard is the chiller package itself, from the chilled water and condenser water connections (or, for air-cooled units, the chilled water connections only) through the integral power and control terminations. Field-installed piping, valves, strainers, flow meters, and isolation devices on the connected loops are covered in [[syncs/hydronic-piping]]. The cooling tower and condenser water heat rejection system, including the tower itself and its sump piping, are covered in the cooling tower standard. The chilled water distribution beyond the chiller connections, including primary/secondary decoupling, distribution pumps, and air separation, is covered in [[syncs/hydronic-piping]] and [[syncs/hvac-pumps]].
+
+Performance rating shall conform to AHRI 550/590 (I-P) or AHRI 551/591 (SI) for water-chilling packages. Sound rating shall conform to AHRI 575. Energy efficiency shall meet or exceed the minimums of ANSI/ASHRAE/IES 90.1 for the applicable chiller type, capacity, and condenser type. Refrigerant safety and machinery room requirements shall conform to ASHRAE 15. Refrigerant designation and safety classification shall conform to ASHRAE 34. Pressure vessels (evaporator and condenser shells) shall conform to ASME Section VIII, Division 1. Refrigerant piping integral to the package shall conform to ASME B31.5. Electrical safety listing shall be UL 1995 or UL 60335-2-40 as accepted by the Authority Having Jurisdiction. Field electrical installation shall conform to NFPA 70 (NEC) Article 440.
+
+# Referenced Standards
+
+Equipment, materials, and installation shall comply with the latest adopted edition of each of the following unless a specific edition is cited. Where conflicts exist between referenced standards, the more stringent requirement shall govern unless the Engineer of Record directs otherwise in writing.
+
+| Standard | Title |
+|----------|-------|
+| ANSI/AHRI 550/590 (I-P) | Performance Rating of Water-Chilling and Heat Pump Water-Heating Packages Using the Vapor Compression Cycle |
+| ANSI/AHRI 551/591 (SI) | Performance Rating of Water-Chilling and Heat Pump Water-Heating Packages Using the Vapor Compression Cycle (SI Units) |
+| ANSI/AHRI 575 | Method of Measuring Machinery Sound Within an Equipment Space |
+| ANSI/ASHRAE/IES 90.1 | Energy Standard for Buildings Except Low-Rise Residential Buildings |
+| ANSI/ASHRAE 15 | Safety Standard for Refrigeration Systems |
+| ANSI/ASHRAE 34 | Designation and Safety Classification of Refrigerants |
+| ANSI/ASHRAE 188 | Legionellosis: Risk Management for Building Water Systems |
+| ASME B31.5 | Refrigeration Piping and Heat Transfer Components |
+| ASME Boiler and Pressure Vessel Code, Section VIII, Division 1 | Rules for Construction of Pressure Vessels |
+| UL 1995 | Heating and Cooling Equipment |
+| UL 60335-2-40 | Safety of Household and Similar Electrical Appliances — Particular Requirements for Electrical Heat Pumps, Air-Conditioners, and Dehumidifiers |
+| NFPA 70 | National Electrical Code (Article 440 — Air-Conditioning and Refrigerating Equipment) |
+| IBC | International Building Code (seismic restraint per applicable edition) |
+| ASCE 7 | Minimum Design Loads and Associated Criteria for Buildings and Other Structures |
+| 40 CFR Part 82 | EPA Refrigerant Management — Stratospheric Ozone Protection |
+| EPA SNAP Program | Significant New Alternatives Policy listings for acceptable refrigerants |
+| NEMA MG 1 | Motors and Generators (Part 31 — Definite Purpose Inverter-Fed Polyphase Motors) |
+| NEMA 250 | Enclosures for Electrical Equipment (1000 Volts Maximum) |
+| AHRI Guideline N | Assignment of Refrigerant Container Colors |
+| AHRI Guideline E | Fouling Factors — A Survey of Their Application in Today's Air-Conditioning and Refrigeration Industry |
+
+Where the project is located in a jurisdiction that has adopted local energy codes more stringent than ASHRAE 90.1 (for example, Title 24 in California, Stretch Code amendments in the Northeast, or local high-performance building ordinances), the local efficiency requirement shall govern.
+
+# Submittals
+
+## Action Submittals
+
+The Contractor shall submit the following for the Engineer's review and acceptance prior to procurement. Fabrication and shipment shall not proceed until action submittals have been reviewed and returned.
+
+- Manufacturer's product data sheets and catalog cuts for each chiller, including model designation, refrigerant, dimensional and weight data (operating and shipping), and identification of all factory-mounted accessories
+- Certified AHRI performance data per AHRI 550/590 (or 551/591) at the project design conditions, including full-load efficiency (kW/ton and COP), IPLV.IP (or NPLV per AHRI 550/590-2023 path), and the performance at the specific design entering and leaving water temperatures and fouling factors
+- Off-design performance data showing capacity and efficiency at part-load points across the operating envelope, including operation at minimum load and at the design wet-bulb (for water-cooled) or design dry-bulb (for air-cooled) approach to ambient
+- Refrigerant designation per ASHRAE 34, safety classification, system charge weight, ASHRAE 15 occupancy classification for the machinery room, and refrigerant monitoring requirements
+- Sound power level data per AHRI 575 in octave bands from 63 Hz through 8 kHz, and sound pressure level at 30 ft (10 m) and at the nearest noise-sensitive receptor
+- Compressor data including type, number of compressors and refrigerant circuits, compressor drive type (hermetic, semi-hermetic, open-drive, magnetic-bearing oil-free), and operating speed or speed range for variable-speed compressors
+- Evaporator data including shell-and-tube construction, tube material and gauge, water-side and refrigerant-side pressure drop, water-side fouling factor used in selection, and minimum and maximum allowable flow rates
+- Condenser data including (for water-cooled) shell-and-tube construction matching the evaporator data plus condenser water flow rate, pressure drop, and fouling factor, or (for air-cooled) coil construction, fan arrangement, ambient air flow, and the design ambient dry-bulb
+- Electrical data including unit nameplate voltage, FLA, MCA (minimum circuit ampacity), MOCP (maximum overcurrent protection), inrush current, starter type (across-the-line, solid-state soft-start, VFD), and short-circuit current rating (SCCR)
+- Starter or integral VFD data sheets where furnished as part of the chiller package
+- Unit controller product data including the integral microprocessor, operator interface, network communications (BACnet, Modbus, LonWorks) and points list
+- Refrigerant relief device data including relief pressure setting, capacity, and vent piping recommendations per ASHRAE 15
+- Lifting and rigging diagrams identifying lift points and operating and shipping weights
+- Seismic restraint calculations and details where required by the applicable building code
+- Coordination drawings showing chiller location, required service clearances (tube pull, compressor service, control panel access), and the integration of refrigerant relief vent piping with the machinery room
+
+```datasheet
+label: Action Submittals Required
+type: checkbox
+options:
+ - "Product data and configuration"
+ - "Certified AHRI 550/590 (or 551/591) performance data at design conditions"
+ - "Part-load performance and IPLV.IP / NPLV documentation"
+ - "Refrigerant data (ASHRAE 34 designation, charge, machinery room classification)"
+ - "Sound power data per AHRI 575"
+ - "Compressor data"
+ - "Evaporator data"
+ - "Condenser data"
+ - "Electrical data (FLA, MCA, MOCP, SCCR, starter or VFD)"
+ - "Unit controller product data and BAS points list"
+ - "Refrigerant relief device data and vent recommendations"
+ - "Lifting and rigging diagrams with weights"
+ - "Seismic restraint calculations"
+ - "Coordination drawings with service clearances"
+default: "Product data and configuration"
+```
+
+## Closeout Submittals
+
+At substantial completion, the Contractor shall provide the following before the chiller is accepted.
+
+- Manufacturer's installation, operation, and maintenance manual covering the as-shipped configuration
+- As-built nameplate data including serial number, model number, manufactured date, refrigerant type and factory charge weight, and the installed motor and starter serial numbers
+- Factory test reports (run test, electrical test, leak test, and where specified, witnessed performance or sound test)
+- Field startup report by the manufacturer's factory-authorized service representative, including measured chilled water flow, condenser water flow (water-cooled), entering and leaving water temperatures, ambient conditions (air-cooled), compressor amperage, oil pressure, refrigerant pressures, and superheat/subcooling
+- Refrigerant charge verification and any field-added refrigerant logged by type, quantity, and date
+- BAS integration documentation including points list as-built, mapping to the BAS, and verified communication
+- Warranty documentation correlating serial number, startup date, and warranty expiration
+- Recommended spare parts list with manufacturer part numbers
+- Training records for Owner's operating personnel
+
+# Quality Assurance
+
+## Manufacturer Qualifications
+
+Chillers shall be the products of a manufacturer with a minimum of fifteen years of continuous experience designing and producing the specific chiller type and size range required for this project. The manufacturer shall maintain an ISO 9001 certified quality management system. Parts and factory-authorized service shall be available for the chiller model line for a minimum of twenty years from the date of manufacture. Local factory-authorized service shall be available within a four-hour response radius of the project site for startup, warranty service, and emergency response.
+
+## AHRI Certification
+
+Each chiller shall be a model that participates in the AHRI Water-Chilling Packages Certification Program covering AHRI 550/590 and AHRI 551/591. Catalog ratings shall be certified by AHRI; non-certified ratings are not acceptable for compliance with this standard.
+
+```datasheet
+label: AHRI Certification Required
+type: radio
+options:
+ - "AHRI 550/590 (I-P) certified"
+ - "AHRI 551/591 (SI) certified"
+ - "Both I-P and SI certifications"
+default: "AHRI 550/590 (I-P) certified"
+```
+
+## ASME and Listing Requirements
+
+The evaporator and condenser shells (and any other refrigerant-containing pressure vessels above the ASME Section VIII Division 1 size threshold) shall be designed, fabricated, inspected, and stamped in accordance with ASME Section VIII, Division 1. The "U" stamp and the manufacturer's data report (Form U-1) shall be provided. The complete chiller package shall be listed and labeled to UL 1995 or UL 60335-2-40 by a Nationally Recognized Testing Laboratory.
+
+```datasheet
+label: Code Stamps and Listings
+type: checkbox
+options:
+ - "ASME 'U' stamp on evaporator"
+ - "ASME 'U' stamp on condenser (water-cooled)"
+ - "UL listing of complete chiller package"
+ - "ETL or CSA listing (where accepted by AHJ in lieu of UL)"
+ - "Manufacturer's Data Report (U-1) furnished for each ASME vessel"
+default: "ASME 'U' stamp on evaporator"
+```
+
+## Single-Source Responsibility
+
+The compressor(s), evaporator, condenser, refrigerant charge, oil charge, unit controller, integral starter or variable frequency drive, and all factory-mounted accessories shall be furnished as a coordinated assembly by a single chiller manufacturer. Field assembly of major components from separate suppliers is not acceptable. The manufacturer shall be responsible for the performance, reliability, and warranty of the complete package.
+
+## Factory-Authorized Startup
+
+Initial startup and commissioning of each chiller shall be performed by the manufacturer's factory-trained and factory-authorized service technician. The startup technician shall be on site for the duration of the initial fill, leak check, oil and refrigerant verification, controls programming, and the functional performance test. The Contractor shall not start the chiller for any purpose prior to manufacturer's startup, except for short uncoupled motor rotation checks performed under the manufacturer's written instructions.
+
+## Pre-Installation Conference
+
+A pre-installation conference shall be held before chiller installation begins, attended by the mechanical contractor, the electrical contractor, the controls contractor, the TAB agent, the chiller manufacturer's representative, and the Owner's representative. Agenda shall include rigging and setting sequence, structural and pad coordination, refrigerant relief vent routing, chilled water and condenser water connection sequence, electrical service and SCCR coordination, BAS integration, ASHRAE 15 machinery room provisions, and the startup schedule.
+
+# Environmental and Service Conditions
+
+## Installation Location and Environment
+
+```datasheet
+label: Chiller Installation Location
+type: select
+options:
+ - "Indoor — mechanical room (water-cooled)"
+ - "Indoor — penthouse or mechanical mezzanine"
+ - "Outdoor — at-grade pad (air-cooled)"
+ - "Outdoor — roof curb or structural steel platform (air-cooled)"
+ - "Outdoor — enclosed mechanical yard with sound walls"
+drawing_ref: true
+default: "Indoor — mechanical room (water-cooled)"
+```
+
+Water-cooled chillers are almost always installed indoors in a dedicated mechanical room or central plant; the cooling tower handles the outdoor heat rejection. Air-cooled chillers are installed outdoors so that the integral condenser can reject heat directly to ambient air; typical locations are an at-grade concrete pad, a structural-steel roof platform, or a roof curb. Locating an air-cooled chiller in a sound-sensitive courtyard or against a building face where condenser air recirculates back into the unit is a common error that both reduces capacity and increases noise complaints. Coordinate location with the architectural and structural drawings and confirm prevailing wind direction and sound receptor locations.
+
+## ASHRAE 15 Machinery Room Classification
+
+Where the chiller is installed indoors, the room shall be classified and arranged in accordance with ASHRAE 15. The room classification depends on the refrigerant type, charge size, and occupancy of adjacent spaces, and may require refrigerant leak detection, mechanical ventilation, separation from occupied spaces, and emergency shutdown. Compliance is the responsibility of the design team; this standard requires that the chiller manufacturer provide the data needed for the classification (refrigerant designation per ASHRAE 34, total system charge weight, recommended refrigerant monitor type and sensor placement).
+
+```datasheet
+label: ASHRAE 15 Machinery Room Classification
+type: select
+options:
+ - "Not applicable — outdoor installation"
+ - "Class A — refrigerant charge below ASHRAE 15 threshold for adjacent occupancy"
+ - "Class T — refrigerant detection and ventilation required"
+ - "Refrigerant monitor and dedicated ventilation provided per ASHRAE 15"
+drawing_ref: true
+default: "Refrigerant monitor and dedicated ventilation provided per ASHRAE 15"
+```
+
+Refrigerant monitoring inside the machinery room shall be provided where required by ASHRAE 15 or the local mechanical code. The monitor shall alarm at the refrigerant concentration limit (RCL) for the applicable refrigerant and initiate the mechanical ventilation and the emergency shutdown of the chiller per the design.
+
+## Ambient Temperature Range
+
+```datasheet
+label: Design Ambient Conditions
+type: select
+options:
+ - "Water-cooled chiller — indoor mechanical room (40–104°F)"
+ - "Air-cooled chiller — standard ambient (95°F design dry-bulb)"
+ - "Air-cooled chiller — high ambient (100–110°F design dry-bulb)"
+ - "Air-cooled chiller — low ambient operation required (below 35°F LAT)"
+drawing_ref: true
+default: "Water-cooled chiller — indoor mechanical room (40–104°F)"
+```
+
+Air-cooled chillers shall be selected at the project's actual design dry-bulb temperature, not at the 95°F AHRI rating point. A chiller selected only at 95°F and installed in a desert climate with a 110°F design dry-bulb will deliver substantially less capacity at peak conditions. Where the chiller is expected to operate at low ambient temperatures (winter operation for process cooling, data centers, or buildings with year-round cooling load), the unit shall be furnished with the manufacturer's low-ambient package: head pressure control by condenser fan cycling or VFD control of condenser fans, and the appropriate refrigerant charge management.
+
+## Altitude
+
+```datasheet
+label: Installation Altitude
+type: select
+options:
+ - "Below 3,000 ft — no derating required"
+ - "3,000–6,000 ft — confirm derating with manufacturer"
+ - "Above 6,000 ft — significant derating; verify capacity and motor rating"
+default: "Below 3,000 ft — no derating required"
+```
+
+Air-cooled chiller capacity is reduced at altitude because the lower air density reduces condenser heat rejection. Electric motor cooling is also reduced at altitude. The chiller manufacturer shall confirm net capacity and motor selection at the project altitude for any installation above 3,000 ft.
+
+# Capacity & Rating Conditions
+
+## Cooling Capacity
+
+```datasheet
+label: Design Cooling Capacity
+type: range
+unit: tons
+drawing_ref: true
+options:
+ min: 50
+ max: 3000
+ setpoints: [50, 75, 100, 125, 150, 200, 250, 300, 400, 500, 700, 1000, 1250, 1500, 2000, 2500, 3000]
+default: 500
+```
+
+Cooling capacity shall be expressed in tons of refrigeration (1 ton = 12,000 Btu/hr) at the design entering and leaving chilled water temperatures, design condenser conditions, and design fouling factors. The selected chiller capacity shall meet or exceed the design block load with no positive tolerance (per AHRI 550/590, the rated capacity is a single point with tolerance permitted by the AHRI test method, not a margin to be applied during selection).
+
+## Chilled Water Rating Conditions
+
+```datasheet
+label: Design Leaving Chilled Water Temperature
+type: range
+unit: °F
+drawing_ref: true
+options:
+ min: 38
+ max: 55
+ setpoints: [38, 40, 42, 44, 45, 48, 50, 52, 55]
+default: 44
+```
+
+```datasheet
+label: Design Chilled Water Temperature Range (ΔT)
+type: range
+unit: °F
+drawing_ref: true
+options:
+ min: 8
+ max: 20
+ setpoints: [8, 10, 12, 14, 16, 18, 20]
+default: 12
+```
+
+Leaving chilled water temperature (LCHW) of 44°F with a 12°F range (56°F entering) is the long-standing comfort-cooling default and is the AHRI 550/590 standard rating point. Lower leaving temperatures (40°F to 42°F) increase cooling tower load and reduce evaporator capacity, but enable smaller chilled water pumps and piping at a given load. Higher leaving temperatures (45°F to 48°F) improve chiller efficiency and are common in projects optimized for low pumping energy or for use with chilled-beam systems. The design ΔT shall be coordinated with the chilled water distribution design in [[syncs/hydronic-piping]] and the air-side coil selections; mismatch between the chiller ΔT and the coil ΔT produces "low ΔT syndrome" in the distribution system.
+
+## Condenser Rating Conditions — Water-Cooled
+
+```datasheet
+label: Water-Cooled Condenser Entering Water Temperature
+type: range
+unit: °F
+drawing_ref: true
+options:
+ min: 65
+ max: 95
+ setpoints: [65, 70, 75, 80, 85, 90, 95]
+default: 85
+```
+
+```datasheet
+label: Water-Cooled Condenser Water Temperature Range (ΔT)
+type: range
+unit: °F
+drawing_ref: true
+options:
+ min: 8
+ max: 15
+ setpoints: [8, 10, 12, 14, 15]
+default: 10
+```
+
+Entering condenser water (ECW) of 85°F with a 10°F range (95°F leaving) is the AHRI 550/590 standard rating point and represents a typical cooling tower performance at the U.S. ASHRAE 1% wet-bulb. Lower ECW improves chiller efficiency substantially — every 1°F reduction in ECW typically reduces full-load kW/ton by approximately 1% to 2% — but requires a larger cooling tower or a lower design wet-bulb. The selected ECW shall be coordinated with the cooling tower selection.
+
+## Condenser Rating Conditions — Air-Cooled
+
+```datasheet
+label: Air-Cooled Condenser Design Ambient Dry-Bulb
+type: range
+unit: °F
+drawing_ref: true
+options:
+ min: 85
+ max: 115
+ setpoints: [85, 90, 95, 100, 105, 110, 115]
+default: 95
+```
+
+Air-cooled chillers are rated at 95°F ambient dry-bulb per AHRI 550/590. Selection at the project's actual design dry-bulb is required where it exceeds the rating condition. Air-cooled chillers experience the largest capacity loss at peak ambient conditions, and the design block load shall be coordinated with the design ambient — not with the AHRI rating ambient — to avoid under-sizing.
+
+## Fouling Factor
+
+```datasheet
+label: Evaporator Fouling Factor
+type: select
+unit: hr·ft²·°F/Btu
+options:
+ - "0.00010 (clean, treated closed-loop CHW — AHRI standard)"
+ - "0.00025 (moderate fouling allowance per AHRI Guideline E)"
+default: "0.00010 (clean, treated closed-loop CHW — AHRI standard)"
+```
+
+```datasheet
+label: Condenser Fouling Factor
+type: select
+unit: hr·ft²·°F/Btu
+options:
+ - "0.00010 (clean, treated water — AHRI standard rating)"
+ - "0.00025 (typical open-loop CW with conventional treatment)"
+ - "0.00050 (aggressive open-loop CW or poor water chemistry)"
+ - "Not applicable — air-cooled condenser"
+default: "0.00025 (typical open-loop CW with conventional treatment)"
+```
+
+Fouling factor is an allowance for heat transfer surface degradation between cleanings. AHRI 550/590 rates chillers at 0.00010 hr·ft²·°F/Btu on both sides; this represents essentially new, clean tubes. Real condenser water service with conventional chemical treatment results in some scale and biofilm accumulation between cleanings, and most design engineers apply a higher condenser fouling factor for selection — typically 0.00025 — to size the chiller for end-of-service-interval performance. The fouling factor used in selection shall be reported on the AHRI submittal and matched to the cleaning interval defined in the operations and maintenance plan.
+
+# Performance & Efficiency
+
+## ASHRAE 90.1 Minimum Efficiency
+
+Each chiller shall meet or exceed the minimum full-load and integrated part-load efficiency requirements of ASHRAE 90.1 for the equipment class (water-cooled vs. air-cooled), compressor type (centrifugal, positive displacement), and capacity range. The applicable minimum shall be confirmed against the ASHRAE 90.1 edition adopted by the local jurisdiction; for many jurisdictions this is ASHRAE 90.1-2019 or 2022. The selected efficiency shall be the more stringent of the local energy code, ASHRAE 90.1, or the project-specific values shown on the contract drawings.
+
+```datasheet
+label: ASHRAE 90.1 Compliance Path
+type: radio
+options:
+ - "Path A — higher full-load efficiency, lower part-load efficiency"
+ - "Path B — lower full-load efficiency, higher part-load efficiency"
+default: "Path B — lower full-load efficiency, higher part-load efficiency"
+```
+
+ASHRAE 90.1 offers two compliance paths for chillers. Path B (the higher part-load path) is generally preferred for typical commercial buildings because most operating hours occur at part load, and total annual chiller energy is dominated by part-load operation. Path A may be appropriate for chillers that operate predominantly at full load (district energy plants, process cooling with steady demand).
+
+## Full-Load Efficiency
+
+```datasheet
+label: Full-Load Efficiency (Water-Cooled)
+type: range
+unit: kW/ton
+drawing_ref: true
+options:
+ min: 0.45
+ max: 0.75
+ setpoints: [0.45, 0.50, 0.55, 0.58, 0.61, 0.64, 0.66, 0.70, 0.75]
+default: 0.55
+```
+
+```datasheet
+label: Full-Load Efficiency (Air-Cooled)
+type: range
+unit: kW/ton
+drawing_ref: true
+options:
+ min: 0.85
+ max: 1.40
+ setpoints: [0.85, 0.95, 1.00, 1.10, 1.15, 1.25, 1.40]
+default: 1.10
+```
+
+Full-load efficiency is expressed as kW/ton (lower is better) or COP (higher is better). Water-cooled centrifugal chillers at standard AHRI conditions commonly achieve 0.50 to 0.60 kW/ton, with high-efficiency centrifugal machines reaching 0.45 kW/ton or lower at the rating point. Water-cooled screw chillers typically achieve 0.55 to 0.65 kW/ton. Air-cooled chillers are inherently less efficient because of the higher condensing temperature dictated by air-side heat transfer, and typical full-load efficiency is 0.95 to 1.15 kW/ton for screw chillers and 1.10 to 1.30 kW/ton for scroll chillers. The values shown above are typical and shall be coordinated with the ASHRAE 90.1 minimum.
+
+## Integrated Part-Load Value (IPLV.IP)
+
+```datasheet
+label: IPLV.IP (Integrated Part-Load Value, Water-Cooled)
+type: range
+unit: kW/ton
+drawing_ref: true
+options:
+ min: 0.30
+ max: 0.60
+ setpoints: [0.30, 0.35, 0.40, 0.45, 0.50, 0.55, 0.60]
+default: 0.40
+```
+
+```datasheet
+label: IPLV.IP (Integrated Part-Load Value, Air-Cooled)
+type: range
+unit: kW/ton
+drawing_ref: true
+options:
+ min: 0.55
+ max: 1.10
+ setpoints: [0.55, 0.65, 0.75, 0.85, 0.95, 1.10]
+default: 0.85
+```
+
+IPLV.IP is a single-number weighted average efficiency at 100%, 75%, 50%, and 25% of full load with corresponding condenser conditions, computed per AHRI 550/590. It is the most commonly reported indicator of part-load performance and is the basis of ASHRAE 90.1 Path B compliance. IPLV.IP is computed at the AHRI standard rating point and assumes a single, isolated chiller; it does not directly represent annual energy at the project. For buildings with unusual load profiles (year-round cooling, low minimum load, or chiller plants with sequencing), the Engineer should also evaluate the chiller at the specific NPLV (non-standard part-load value) condition reflecting the actual sequence and condenser-water reset strategy.
+
+## Performance Tolerance and Penalty
+
+```datasheet
+label: Performance Compliance
+type: radio
+options:
+ - "Manufacturer's certified AHRI rating with no field performance penalty"
+ - "Performance penalty for capacity below specified, efficiency above specified, or both"
+ - "Witnessed factory performance test required (large or critical machines)"
+default: "Manufacturer's certified AHRI rating with no field performance penalty"
+```
+
+For critical applications — district energy, data centers, central plants serving multiple buildings — the specification may include a performance penalty clause that imposes a monetary deduction if the field-measured kW/ton at the design condition exceeds the certified rating, or witness factory performance testing on the specific machine before shipment. For most commercial projects, the manufacturer's AHRI-certified rating is sufficient.
+
+# Refrigerant
+
+## Refrigerant Selection
+
+```datasheet
+label: Refrigerant
+type: select
+options:
+ - "R-134a (HFC, A1, GWP 1430) — common in centrifugal chillers, regulated phase-down underway"
+ - "R-513A (HFO/HFC blend, A1, GWP 631) — drop-in alternative for R-134a"
+ - "R-1233zd(E) (HFO, A1, GWP < 1) — ultra-low-pressure centrifugal applications"
+ - "R-1234ze(E) (HFO, A2L, GWP < 1) — low-pressure centrifugal alternative"
+ - "R-32 (HFC, A2L, GWP 675) — small to medium scroll/screw air-cooled"
+ - "R-454B (HFO/HFC blend, A2L, GWP 466) — replacement for R-410A in scroll/screw"
+ - "R-410A (HFC, A1, GWP 2088) — legacy scroll/screw, phasing out under EPA rules"
+default: "R-513A (HFO/HFC blend, A1, GWP 631) — drop-in alternative for R-134a"
+```
+
+Refrigerant selection is governed by the EPA Significant New Alternatives Policy (SNAP) program, the American Innovation and Manufacturing (AIM) Act phase-down of HFCs, and the chiller manufacturer's product line. R-134a remains widely available for new equipment but is subject to the HFC phase-down; R-513A is a near-drop-in lower-GWP replacement with similar performance and ASHRAE 34 A1 (nontoxic, nonflammable) safety classification. R-1233zd(E) and R-1234ze(E) are low-pressure HFO refrigerants used in centrifugal chillers and offer GWP below 1; R-1234ze(E) is A2L (mildly flammable) and requires additional safety provisions per ASHRAE 15. R-32 and R-454B are A2L refrigerants common in newer scroll and screw equipment.
+
+The selected refrigerant shall (1) be currently EPA SNAP-approved for the equipment type, (2) be supported by the chiller manufacturer for the equipment model, (3) be permitted by the local jurisdiction's adopted edition of ASHRAE 15 for the machinery room classification, and (4) align with the Owner's long-term refrigerant strategy where the Owner has expressed one.
+
+## Refrigerant Charge and Containment
+
+```datasheet
+label: Refrigerant Charge Containment
+type: checkbox
+options:
+ - "Factory-charged with operating refrigerant quantity"
+ - "Factory holding charge of dry nitrogen for shipment, field-charged at startup"
+ - "Refrigerant isolation valves at evaporator and condenser for pump-down service"
+ - "Pump-out / storage receiver provided for field service refrigerant recovery"
+default: "Factory-charged with operating refrigerant quantity"
+```
+
+Smaller chillers (scroll, smaller screw) typically ship factory-charged with the operating refrigerant; larger chillers (centrifugal and large screw) frequently ship with a nitrogen holding charge and are field-charged at startup. Where the chiller will be field-charged, the manufacturer's startup technician shall be responsible for the charging and the refrigerant shall be supplied as part of the chiller package.
+
+## Refrigerant Relief
+
+Each refrigerant-containing pressure vessel shall be protected by a relief device sized and selected per ASHRAE 15 and ASME Section VIII. Relief devices shall discharge to outdoors through a vent line sized per ASHRAE 15. The relief vent line is part of the field-installed scope and shall be coordinated with the chiller's relief device location, capacity, and recommended pipe size.
+
+```datasheet
+label: Refrigerant Relief Vent Routing
+type: radio
+options:
+ - "Direct to outdoors through dedicated relief vent line sized per ASHRAE 15"
+ - "Through common refrigerant relief manifold serving multiple chillers"
+ - "Discharge into machinery room (only where permitted by ASHRAE 15 charge limits)"
+drawing_ref: true
+default: "Direct to outdoors through dedicated relief vent line sized per ASHRAE 15"
+```
+
+# Compressor
+
+## Compressor Type
+
+```datasheet
+label: Compressor Type
+type: select
+options:
+ - "Centrifugal — hermetic, fixed-speed (small to large water-cooled)"
+ - "Centrifugal — hermetic, variable-speed (VFD)"
+ - "Centrifugal — open-drive (very large industrial, gear-driven)"
+ - "Centrifugal — magnetic-bearing oil-free (premium efficiency, low first cost ownership)"
+ - "Screw — semi-hermetic, fixed-speed"
+ - "Screw — semi-hermetic, variable-speed (VFD)"
+ - "Scroll — hermetic, fixed-speed (small air-cooled, multiple compressors per circuit)"
+drawing_ref: true
+default: "Centrifugal — hermetic, variable-speed (VFD)"
+```
+
+Compressor type is the single most consequential machine-level decision and is generally tied to chiller size and configuration. Centrifugal compressors dominate the water-cooled market above approximately 200 tons because of their high efficiency, smooth modulation, and durability; below 200 tons, screw compressors are competitive on first cost and efficiency. Scroll compressors dominate air-cooled chillers below approximately 200 tons, with multiple scrolls staged across one or more refrigerant circuits to provide capacity modulation and redundancy. Magnetic-bearing oil-free centrifugal compressors eliminate the oil system entirely, offer excellent part-load efficiency through high-speed operation on magnetic bearings, and are particularly attractive for buildings with high part-load operating hours.
+
+## Number of Compressors and Refrigerant Circuits
+
+```datasheet
+label: Number of Refrigerant Circuits
+type: radio
+options:
+ - "Single circuit, single compressor"
+ - "Single circuit, multiple compressors (tandem or trio scroll)"
+ - "Dual circuit, single compressor per circuit (redundancy)"
+ - "Dual circuit, multiple compressors per circuit"
+drawing_ref: true
+default: "Dual circuit, multiple compressors per circuit"
+```
+
+Redundancy is a function of the project's tolerance for outage. A single-circuit chiller is the simplest and most efficient configuration, but a refrigerant leak or compressor failure removes 100% of the unit's capacity. A dual-circuit chiller continues to operate at approximately 50% capacity when one circuit is offline, which is acceptable for many commercial applications and shifts the redundancy decision toward a single chiller rather than two smaller chillers. For critical applications, dual-circuit chillers and multiple chillers in parallel are both common.
+
+## Variable-Speed Operation
+
+```datasheet
+label: Variable-Speed Compressor Drive
+type: radio
+options:
+ - "Yes — VFD on compressor (variable-speed centrifugal or screw)"
+ - "Yes — magnetic-bearing oil-free with inherent variable speed"
+ - "No — fixed-speed compressor with mechanical capacity modulation"
+default: "Yes — VFD on compressor (variable-speed centrifugal or screw)"
+```
+
+Variable-speed compressor drive substantially improves part-load efficiency by allowing the compressor to slow as load drops, instead of throttling refrigerant flow with inlet guide vanes (centrifugal) or slide valves (screw) while running at full speed. For typical commercial cooling load profiles — significant operating hours below 50% load — a VFD payback is often two to four years. The trade-off is increased first cost, additional harmonic distortion on the building electrical service that may require mitigation, and the VFD's own service requirements.
+
+## Compressor Service Access
+
+The compressor shall be arranged for in-place service of routine items (oil filters, sensors, terminations) without removing the compressor from the chiller, and shall be removable from the chiller for major service (rebuild or replacement) through a defined service path. The Contractor shall coordinate machinery room clearances with the manufacturer's required service access; the typical centrifugal compressor service clearance is the full length of the chiller plus space for the compressor rotor or impeller withdrawal.
+
+# Evaporator
+
+## Evaporator Construction
+
+```datasheet
+label: Evaporator Type
+type: radio
+options:
+ - "Shell-and-tube, flooded (refrigerant on shell side, water in tubes) — centrifugal/screw"
+ - "Shell-and-tube, direct-expansion (refrigerant in tubes, water on shell side) — screw/scroll"
+ - "Brazed plate (compact, low-charge) — small scroll air-cooled"
+drawing_ref: true
+default: "Shell-and-tube, flooded (refrigerant on shell side, water in tubes) — centrifugal/screw"
+```
+
+Flooded shell-and-tube evaporators are standard for centrifugal and most screw chillers and provide the highest efficiency because of their large refrigerant-side heat transfer area and their ability to operate at a small refrigerant-to-water temperature approach. Direct-expansion (DX) evaporators are used in many screw and scroll chillers and have a smaller refrigerant charge per ton at the cost of a slightly larger approach. Brazed-plate evaporators are common in small scroll air-cooled chillers and offer compactness and very low refrigerant charge.
+
+## Evaporator Tubes
+
+```datasheet
+label: Evaporator Tube Material
+type: select
+options:
+ - "Copper, enhanced (internally and externally enhanced surface)"
+ - "Copper-nickel (90/10) — aggressive or contaminated water"
+ - "Stainless steel — process water or unusual chemistry"
+ - "Titanium — seawater or extremely aggressive applications"
+default: "Copper, enhanced (internally and externally enhanced surface)"
+```
+
+Copper with enhanced surfaces (rifled, integrally finned, or otherwise textured) is the standard evaporator tube and provides excellent heat transfer in clean treated chilled water service. Copper-nickel, stainless steel, and titanium tubes shall be specified where the chilled water source is non-standard — for example, process water with chloride content, recovered water, or geothermal source loops with aggressive chemistry.
+
+## Evaporator Water-Side Provisions
+
+```datasheet
+label: Chilled Water Connections
+type: select
+options:
+ - "Grooved (Victaulic-type) couplings — common for smaller chillers"
+ - "Flanged (ANSI Class 150 minimum)"
+ - "Flanged (ANSI Class 300) — high-pressure systems"
+drawing_ref: true
+default: "Flanged (ANSI Class 150 minimum)"
+```
+
+```datasheet
+label: Evaporator Water-Side Provisions
+type: checkbox
+options:
+ - "Marine waterbox (removable cover for tube cleaning)"
+ - "Standard waterbox"
+ - "Insulated waterbox covers (factory)"
+ - "Drain and vent connections at waterbox"
+ - "Differential pressure taps for flow verification"
+ - "Strainer (basket type) on chilled water supply"
+default: "Marine waterbox (removable cover for tube cleaning)"
+```
+
+Marine waterboxes — removable end covers that allow the tubes to be brush-cleaned without disconnecting the chilled water piping — are recommended for chillers in service longer than 10 years where periodic tube cleaning is planned. Standard waterboxes are acceptable for chillers in clean treated closed-loop service where tube cleaning will be infrequent.
+
+## Evaporator Insulation
+
+```datasheet
+label: Evaporator Insulation
+type: radio
+options:
+ - "Factory-applied closed-cell elastomeric foam, 3/4 in. minimum"
+ - "Factory-applied closed-cell elastomeric foam, 1 in. (low-temp applications)"
+ - "Field-applied insulation by mechanical contractor"
+default: "Factory-applied closed-cell elastomeric foam, 3/4 in. minimum"
+```
+
+The evaporator and connected piping operate below dew-point and require continuous vapor-tight insulation. Factory-applied closed-cell foam on the evaporator shell, waterboxes, and refrigerant suction lines is strongly preferred because the factory installation eliminates field labor on a complex shape and ensures continuous coverage. Field-applied insulation is acceptable only where access for the factory application is impractical.
+
+# Condenser
+
+## Water-Cooled Condenser
+
+```datasheet
+label: Water-Cooled Condenser Construction
+type: radio
+options:
+ - "Shell-and-tube, refrigerant in shell, water in tubes"
+ - "Shell-and-tube with subcooler section"
+default: "Shell-and-tube with subcooler section"
+```
+
+```datasheet
+label: Condenser Tube Material
+type: select
+options:
+ - "Copper, enhanced (standard treated condenser water)"
+ - "Copper-nickel (90/10) — open-loop CW with aggressive chemistry"
+ - "Titanium — coastal applications, recovered water, or severe corrosion concerns"
+default: "Copper, enhanced (standard treated condenser water)"
+```
+
+Water-cooled condenser construction parallels the evaporator: shell-and-tube with copper or alloy tubes, marine or standard waterboxes, flanged or grooved water connections, and waterbox vents and drains. A subcooler section at the condenser outlet increases refrigerant liquid subcooling, improves cycle efficiency, and is standard on most centrifugal and screw chillers.
+
+```datasheet
+label: Condenser Water-Side Provisions
+type: checkbox
+options:
+ - "Marine waterbox (removable cover for tube cleaning)"
+ - "Standard waterbox"
+ - "Drain and vent connections at waterbox"
+ - "Differential pressure taps for flow verification"
+ - "Strainer (basket type) on condenser water supply"
+ - "Automatic tube brush cleaning system (continuous tube cleaning)"
+default: "Marine waterbox (removable cover for tube cleaning)"
+```
+
+Marine waterboxes are strongly recommended for water-cooled condensers because open-loop condenser water service produces scale and biofilm on tube interiors that must be brushed out periodically. Automatic tube brush cleaning systems circulate small brushes through the condenser tubes continuously and substantially reduce manual cleaning labor; they are common on large central plants in continuous service.
+
+## Air-Cooled Condenser
+
+```datasheet
+label: Air-Cooled Condenser Coil Construction
+type: select
+options:
+ - "Copper tube, aluminum fin (standard)"
+ - "All-aluminum microchannel (compact, low refrigerant charge)"
+ - "Copper tube, copper fin (premium corrosion resistance)"
+ - "E-coated aluminum or copper fin (corrosive environment protection)"
+drawing_ref: true
+default: "Copper tube, aluminum fin (standard)"
+```
+
+Air-cooled condenser coils consist of refrigerant-carrying tubes (copper or aluminum microchannel) with extended fins (aluminum, copper, or coated) to maximize air-side heat transfer area. Standard copper-tube aluminum-fin construction is appropriate for most outdoor installations. Microchannel all-aluminum coils are compact, contain less refrigerant per ton, and resist some types of corrosion, but a small leak in a microchannel section typically requires replacement of the entire coil segment because individual tubes are not field-repairable. E-coated coils provide additional corrosion protection for coastal, urban, and industrial environments where airborne chlorides, sulfides, or particulates would otherwise degrade the standard fin material.
+
+```datasheet
+label: Condenser Fan Type
+type: radio
+options:
+ - "Direct-drive axial propeller fans, fixed-speed (standard)"
+ - "Direct-drive axial propeller fans with EC motors (variable-speed standard)"
+ - "VFD-controlled fans (head pressure control, sound reduction)"
+drawing_ref: true
+default: "VFD-controlled fans (head pressure control, sound reduction)"
+```
+
+Condenser fans dominate the off-design noise signature of an air-cooled chiller and are also a significant parasitic load. Variable-speed condenser fans (either EC motor-equipped fans or VFD-driven AC fans) allow head pressure control as ambient temperature drops, reduce fan power at part load, and substantially reduce off-design sound — especially at night when both ambient temperature and noise constraints favor low fan speed. Fixed-speed fans cycled on/off by head pressure controls are acceptable but produce step changes in noise and capacity.
+
+# Power & Starter
+
+## Electrical Service
+
+```datasheet
+label: Unit Nameplate Voltage
+type: select
+options:
+ - "208V / 3-phase / 60Hz"
+ - "230V / 3-phase / 60Hz"
+ - "460V / 3-phase / 60Hz"
+ - "480V / 3-phase / 60Hz"
+ - "600V / 3-phase / 60Hz"
+ - "2300V / 3-phase / 60Hz (medium-voltage centrifugal, very large)"
+ - "4160V / 3-phase / 60Hz (medium-voltage centrifugal, very large)"
+drawing_ref: true
+default: "460V / 3-phase / 60Hz"
+```
+
+Voltage selection shall match the building electrical service available at the chiller location. Low-voltage 460V or 480V service is standard for chillers up to approximately 1,000 tons. Medium-voltage service (2,300V or 4,160V) is used for very large centrifugal chillers where the low-voltage motor and feeder size become impractical; this is a system-level decision coordinated with the electrical engineer and may require dedicated transformers, switchgear, and operator qualification considerations.
+
+## Starter Type
+
+```datasheet
+label: Starter Type
+type: select
+options:
+ - "Across-the-line (full-voltage) magnetic starter — small chillers only"
+ - "Solid-state soft starter — reduced inrush, constant-speed"
+ - "Wye-delta or auto-transformer reduced-voltage starter — legacy alternative"
+ - "VFD (variable-speed compressor)"
+ - "Magnetic-bearing oil-free integral drive"
+drawing_ref: true
+default: "VFD (variable-speed compressor)"
+```
+
+Across-the-line starting produces compressor inrush currents on the order of six to eight times full-load amperes and can cause unacceptable voltage dips on the building service for any chiller above approximately 100 tons. Solid-state soft starters reduce inrush at the cost of higher first cost and additional heat to manage. VFDs eliminate the inrush problem entirely (VFD starting current is essentially full-load), provide variable-speed compressor operation for part-load efficiency, and are the standard starter type for new chillers above approximately 75 tons. Coordinate with the electrical engineer for short-circuit current rating (SCCR), maximum inrush, and harmonic compatibility with the building service.
+
+```datasheet
+label: Starter Location
+type: radio
+options:
+ - "Integral to chiller (factory-mounted, factory-wired)"
+ - "Unit-mounted (mounted on chiller frame, field power termination only)"
+ - "Remote (free-standing or wall-mounted, field-wired between starter and chiller)"
+drawing_ref: true
+default: "Integral to chiller (factory-mounted, factory-wired)"
+```
+
+Factory-mounted and factory-wired integral starters and VFDs eliminate field power wiring between the starter and the compressor and avoid the cable length and filtering issues associated with remote-mounted VFDs. Remote starters are appropriate where machinery room thermal load must be minimized, where the starter or VFD requires its own cooled enclosure, or where service access to the starter is poor at the chiller location. Where a VFD is remote-mounted, the cable length and motor filtering requirements of [[syncs/hvac-variable-frequency-drives]] shall be applied to the chiller-to-VFD run.
+
+## Electrical Safety
+
+```datasheet
+label: Short-Circuit Current Rating (SCCR)
+type: select
+unit: kA
+options:
+ - "5 kA"
+ - "10 kA"
+ - "14 kA"
+ - "25 kA"
+ - "35 kA"
+ - "65 kA"
+ - "100 kA"
+drawing_ref: true
+default: "65 kA"
+```
+
+The chiller's SCCR shall meet or exceed the available fault current at the chiller line-side terminals as established by the electrical engineer's short-circuit study. SCCR below the available fault current is a code violation under NFPA 70 and a safety hazard. Coordinate the SCCR with the upstream protection coordination study.
+
+# Controls
+
+## Unit Controller
+
+Each chiller shall be furnished with an integral microprocessor-based unit controller that performs all safeties, capacity control, refrigerant management, and condenser management. The controller shall include an operator interface (graphical color display preferred, monochrome acceptable for smaller chillers) mounted on the chiller for local operation. Controller programming shall be the manufacturer's standard with all parameters required for proper operation at the design conditions configured at the factory.
+
+```datasheet
+label: Unit Controller Features
+type: checkbox
+options:
+ - "Color graphical operator interface (mounted on chiller)"
+ - "Full alarm and event history (minimum 30 days)"
+ - "Operating data trends (compressor, evaporator, condenser)"
+ - "Password-protected service parameters"
+ - "Multi-language support"
+ - "USB or Ethernet port for data export"
+default: "Color graphical operator interface (mounted on chiller)"
+```
+
+## BAS Integration and Communication
+
+```datasheet
+label: BAS Communication Protocol
+type: select
+options:
+ - "BACnet/IP (preferred for new buildings)"
+ - "BACnet MS/TP (RS-485)"
+ - "Modbus TCP"
+ - "Modbus RTU (RS-485)"
+ - "LonWorks (LON FT-10)"
+ - "Proprietary chiller manufacturer's protocol with BACnet gateway"
+drawing_ref: true
+default: "BACnet/IP (preferred for new buildings)"
+```
+
+BACnet/IP is the preferred protocol for new commercial buildings and is the protocol assumed by [[syncs/building-automation-system]]. The chiller shall be a BACnet-certified Application Specific Controller (B-ASC) at minimum, with the manufacturer's published BACnet PICS (Protocol Implementation Conformance Statement) made available. Modbus and LonWorks remain in service in legacy buildings and may be specified where consistency with an existing BAS is required. Proprietary protocols with vendor-specific gateways shall be avoided where the chiller will outlive the gateway and where future BAS replacement is anticipated.
+
+```datasheet
+label: Chiller BAS Points (typical minimum)
+type: checkbox
+options:
+ - "Chiller enable / disable (BAS to chiller)"
+ - "Chilled water setpoint reset (BAS to chiller)"
+ - "Demand limit (BAS to chiller, % of full load)"
+ - "Run status"
+ - "Active alarm with code"
+ - "Leaving chilled water temperature"
+ - "Entering chilled water temperature"
+ - "Leaving condenser water temperature (water-cooled)"
+ - "Entering condenser water temperature (water-cooled)"
+ - "Outdoor air temperature (air-cooled)"
+ - "Compressor amperage (% RLA)"
+ - "Compressor speed (variable-speed)"
+ - "Refrigerant evaporator and condenser pressures"
+ - "Cumulative operating hours"
+ - "Cumulative starts"
+default: "Chiller enable / disable (BAS to chiller)"
+```
+
+## Chilled Water Reset and Sequencing
+
+Where multiple chillers operate in a plant, sequencing and chilled water temperature reset shall be coordinated with the chilled water plant design. The chiller's integral controller shall accept BAS-commanded chilled water setpoint, demand limit, and enable/disable; complex plant sequencing logic (chiller selection, condenser water reset, primary/secondary pump control) resides in the BAS or in a dedicated plant controller, not in the chiller unit controller.
+
+# Sound
+
+## Sound Rating
+
+```datasheet
+label: Sound Rating per AHRI 575
+type: range
+unit: dBA at 30 ft
+drawing_ref: true
+options:
+ min: 55
+ max: 95
+ setpoints: [55, 60, 65, 70, 75, 80, 85, 90, 95]
+default: 75
+```
+
+Sound rating shall be certified per AHRI 575 (machinery room sound) for water-cooled chillers and per AHRI 575 or the manufacturer's equivalent free-field method for air-cooled chillers. The sound rating shall be reported as octave-band sound power levels (63 Hz through 8 kHz) and as A-weighted sound pressure level at the standard distance. For air-cooled chillers, both full-speed and reduced-speed (night setback) sound shall be reported where variable-speed condenser fans are provided.
+
+## Sound Mitigation
+
+```datasheet
+label: Sound Reduction Provisions
+type: checkbox
+options:
+ - "Compressor sound enclosure (factory)"
+ - "Variable-speed condenser fans (air-cooled)"
+ - "Low-noise fan blades and reduced tip speed (air-cooled)"
+ - "Sound attenuation barrier or screen (field-installed)"
+ - "Spring vibration isolators (1 in. minimum static deflection)"
+ - "Flexible piping connections at chiller water connections"
+default: "Spring vibration isolators (1 in. minimum static deflection)"
+```
+
+Air-cooled chillers installed near noise-sensitive boundaries (residential property lines, hospital windows, office facades) frequently require multiple sound mitigation measures: low-noise fan packages, variable-speed fans for night setback, sound walls or screens, and careful site arrangement to direct fan exhaust away from sensitive receptors. The Engineer shall confirm the design sound level at the nearest receptor against the applicable noise ordinance and the project sound criteria.
+
+# Seismic
+
+## Seismic Restraint
+
+```datasheet
+label: Seismic Restraint
+type: radio
+options:
+ - "Required — per IBC and ASCE 7 (verify project seismic design category)"
+ - "Required — essential facility (Ip = 1.5)"
+ - "Not required (low seismic design category)"
+drawing_ref: true
+default: "Required — per IBC and ASCE 7 (verify project seismic design category)"
+```
+
+Where required by the IBC and ASCE 7 based on the seismic design category and equipment importance factor, chillers shall be provided with seismic restraints. Restraints shall be designed to permit the vibration isolators to function normally under operating loads while limiting motion during a seismic event to a level that does not damage attached refrigerant piping, water piping, or electrical connections. Seismic restraint calculations shall be sealed by a professional engineer licensed in the project jurisdiction.
+
+# Accessories & Options
+
+## Factory-Mounted Accessories
+
+```datasheet
+label: Factory-Mounted Accessories
+type: checkbox
+options:
+ - "Integral starter or VFD"
+ - "Chilled water flow switch / proof of flow"
+ - "Condenser water flow switch (water-cooled)"
+ - "Differential pressure switches across evaporator and condenser"
+ - "Refrigerant leak detection sensor (integral)"
+ - "Oil reservoir heater and oil-temperature monitoring"
+ - "Service isolation valves at compressor suction and discharge"
+ - "Power factor correction capacitors"
+ - "Auxiliary contacts for run status, alarm, and remote enable"
+ - "Marine waterboxes (evaporator and condenser)"
+ - "Factory-applied evaporator insulation"
+default: "Chilled water flow switch / proof of flow"
+```
+
+## Heat Recovery Option
+
+```datasheet
+label: Heat Recovery Configuration
+type: radio
+options:
+ - "Not provided"
+ - "Partial heat recovery (auxiliary condenser for domestic preheat or building reheat)"
+ - "Full heat recovery (dual-condenser, simultaneous heating and cooling)"
+default: "Not provided"
+```
+
+Heat recovery chillers reject condenser heat to a useful destination — domestic hot water preheat, building heating loop, swimming pool heating, snow-melt — rather than to a cooling tower or outdoor air. Partial heat recovery uses a small auxiliary condenser to capture a portion of the heat at moderate temperature; full heat recovery uses a complete second condenser to produce heating-temperature water (typically 105°F to 140°F) at the same time the chiller produces chilled water. Heat recovery is highly application-specific and shall be evaluated against the project's coincident heating and cooling loads.
+
+## Free Cooling / Waterside Economizer Integration
+
+```datasheet
+label: Waterside Economizer / Free Cooling
+type: radio
+options:
+ - "Not applicable"
+ - "External plate-and-frame heat exchanger coordinated with chiller bypass"
+ - "Integral refrigerant-side free cooling (thermosiphon, air-cooled chillers)"
+default: "Not applicable"
+```
+
+Where the project includes a waterside economizer (a plate-and-frame heat exchanger that bypasses the chiller when condenser water is cold enough to produce chilled water directly), the chiller controls shall coordinate with the economizer sequence and the chiller shall safely shut down when economizer operation alone meets the load. Some air-cooled chillers include integral refrigerant-side free cooling that uses ambient air at low temperatures to cool the refrigerant directly without running the compressor; this is a manufacturer-specific option useful in cold climates with year-round cooling load.
+
+# Factory Testing
+
+The manufacturer shall perform the following factory tests on each chiller before shipment:
+
+- Pressure test (leak test) of the refrigerant circuit at the manufacturer's specified test pressure, with no detectable leakage
+- Evacuation and vacuum hold of the refrigerant circuit prior to charging or holding-charge fill
+- Hydrostatic test of the water-side circuits (evaporator and condenser) per ASME Section VIII Division 1 requirements
+- Mechanical run test of the assembled chiller — for centrifugal and screw chillers this is a no-load run with the refrigerant circuit charged to verify rotation, oil pressure, vibration, and controller function
+- Electrical test of the integral power and control circuits, including continuity, insulation resistance, and protective function verification
+- Verification of all factory-set safety setpoints (high-pressure cutout, low-pressure cutout, freeze protection, oil pressure, overcurrent)
+
+```datasheet
+label: Factory Test Documentation
+type: checkbox
+options:
+ - "Refrigerant leak test certificate"
+ - "Hydrostatic test certificate (evaporator and condenser)"
+ - "Mechanical run test report"
+ - "Electrical test report"
+ - "Safety setpoint verification record"
+ - "Witnessed performance test (where specified)"
+ - "Witnessed sound test (where specified)"
+default: "Refrigerant leak test certificate"
+```
+
+Witness performance testing is reserved for large centrifugal chillers, district energy applications, mission-critical installations, and projects with tight performance envelopes. Where specified, the witness test shall be conducted at the manufacturer's certified test stand with calibrated instrumentation, at conditions reproducing the design point as closely as the test stand permits, and the Owner's representative and the Engineer shall be given adequate advance notice to attend.
+
+# Field Testing & Commissioning
+
+## Pre-Startup Checks
+
+Before manufacturer's startup, the Contractor shall complete the following with the chiller isolated electrically and hydraulically:
+
+- Verify the chiller has been set on its housekeeping pad, leveled, anchored, and that any seismic restraints are installed per the manufacturer's instructions
+- Verify chilled water and condenser water piping is complete, pressure-tested, flushed, and refilled per [[syncs/hydronic-piping]] and [[syncs/hvac-water-treatment]]
+- Verify all flow switches, pressure taps, and instrumentation are installed and the flow paths through the evaporator and condenser are correct
+- Verify electrical power termination at the chiller is complete, the SCCR is adequate for the available fault current, and ground per [[syncs/grounding-and-bonding]]
+- Verify the refrigerant relief vent piping is installed, routed to outdoors, and supported per ASHRAE 15
+- Verify the BAS communication wiring is installed and the chiller has been added to the BAS database per [[syncs/building-automation-system]]
+- Verify the machinery room ventilation, refrigerant monitor, and emergency shutdown per ASHRAE 15 are installed and functional
+
+## Manufacturer Startup
+
+The manufacturer's factory-authorized service technician shall perform the following:
+
+- Verify factory holding charge or operating refrigerant charge
+- Evacuate the refrigerant circuit if shipped with a holding charge, and charge with the operating refrigerant
+- Verify oil charge and oil temperature; energize oil heater for the manufacturer's specified soak time before first start
+- Confirm rotation direction by jogging the compressor (or by VFD with limited acceleration) before sustained operation
+- Start the chiller and operate at minimum load to verify safeties, alarms, and shutdowns function correctly
+- Bring the chiller up through its operating range to design load (where the connected system permits) and record full operating data
+- Configure controller parameters for the project — chilled water setpoint, demand limit defaults, condenser-water reset (water-cooled), low-ambient operation (air-cooled), and BAS network address
+
+```datasheet
+label: Functional Performance Test
+type: checkbox
+options:
+ - "Chiller starts and reaches steady state on first attempt"
+ - "Chiller operates at design conditions and meets capacity"
+ - "All safety setpoints verified by test (manual or simulated trip)"
+ - "All alarms tested and clear properly"
+ - "BAS communication and points list verified end-to-end"
+ - "Sequence-of-operation tested under BAS control (enable, disable, setpoint, demand limit)"
+ - "Multi-chiller sequencing tested (where multiple chillers)"
+ - "Low-ambient operation tested (air-cooled, where applicable)"
+default: "Chiller starts and reaches steady state on first attempt"
+```
+
+## Owner Training
+
+The manufacturer shall provide a minimum of eight hours of on-site training for the Owner's operating personnel, covering routine operation, the operator interface, alarm response, common maintenance tasks, and refrigerant management requirements. Training shall be scheduled during the substantial completion period when permanent operating personnel are available.
+
+# Installation
+
+## Setting and Anchoring
+
+Chillers shall be set on housekeeping pads designed per [[syncs/concrete-pads]] sized for the operating weight of the chiller, including a full water charge in the evaporator and condenser (water-cooled). The pad shall extend a minimum of 4 in. beyond the chiller footprint on all sides and shall be a minimum of 4 in. above the surrounding floor for drainage and access. Anchor bolts shall be set per the chiller manufacturer's foundation drawing; embedment and bolt size shall be adequate for the operating, wind, and seismic loads where applicable.
+
+For roof-mounted air-cooled chillers, the structural support shall be designed by the structural engineer for the operating weight, the wind loads on the chiller as an exposed structure, the seismic loads, and the dynamic load from condenser fan operation. The Contractor shall provide the actual operating and shipping weights to the structural engineer at the chiller selection stage.
+
+## Service Clearances
+
+```datasheet
+label: Service Clearances Provided
+type: checkbox
+options:
+ - "Tube pull clearance at evaporator end (full evaporator length)"
+ - "Tube pull clearance at condenser end (full condenser length, water-cooled)"
+ - "Compressor service clearance per manufacturer drawing"
+ - "Control panel access clearance (NEC working space)"
+ - "Coil cleaning clearance (air-cooled, all sides per manufacturer)"
+ - "Refrigerant relief vent piping clearance"
+drawing_ref: true
+default: "Tube pull clearance at evaporator end (full evaporator length)"
+```
+
+Tube pull clearance is the single most frequently violated chiller service clearance — the dimension is large (frequently equal to the full evaporator length, often 8 ft to 15 ft) and is required at the end of the chiller opposite the water connections. Installations that omit tube pull clearance commit the building to either cutting tubes in place during retubing or relocating equipment to gain access. Coordinate with the architectural and structural drawings at the design stage; tube pull clearance shall not be sacrificed to fit additional equipment in the room.
+
+For air-cooled chillers, condenser air intake and discharge clearances per the manufacturer's installation manual shall be maintained on all sides. Failure to maintain these clearances causes condenser air recirculation, which substantially raises the effective condensing temperature and degrades capacity and efficiency at peak ambient conditions.
+
+## Water Piping Connections
+
+Chilled water and condenser water piping shall be connected to the chiller per [[syncs/hydronic-piping]]. Pipe size at the chiller shall match the connection size; reductions or expansions in piping shall be made away from the chiller, not at the connection. Flexible connectors shall be provided at both connections to accommodate small misalignments and isolate piping vibration. Isolation valves shall be installed in both connections to permit chiller service without draining the system, and drain valves shall be installed between the isolation valves and the chiller to allow the chiller water side to be drained without disturbing the rest of the system.
+
+## Refrigerant Relief Vent Piping
+
+The refrigerant relief vent piping shall be installed from the chiller relief device(s) to outdoors per ASHRAE 15. The vent line shall be sized so that the back-pressure on the relief device does not exceed the manufacturer's allowable value, shall be supported independently of the chiller, and shall terminate at a location where a refrigerant release will not be drawn into a building outdoor air intake. The terminal shall be provided with a turned-down elbow or weatherproof cap that prevents rain ingress but does not impede flow.
+
+## Insulation of Connected Piping
+
+Chilled water piping connected to the chiller shall be insulated continuously with vapor-tight insulation per [[syncs/hydronic-piping]]. Insulation shall be continuous over flanges, valves, and fittings to prevent condensation, and the vapor barrier shall be continuous and sealed. Discontinuities in chilled water insulation produce condensation that damages floors, ceilings, and adjacent equipment and is one of the most common warranty-period complaints on new chiller installations.
+
+# Refrigerant Management
+
+The Owner is responsible for ongoing refrigerant management under 40 CFR Part 82. The Contractor's responsibilities under this standard are to:
+
+- Document the refrigerant type, total system charge weight, and date of charge on the chiller's nameplate and in the closeout submittals
+- Ensure that any field refrigerant addition is performed only by EPA Section 608 certified technicians
+- Provide refrigerant recovery during any major service that opens the refrigerant circuit; venting of refrigerant to atmosphere is prohibited under EPA rules and constitutes a federal violation
+- Provide the Owner with the refrigerant management documentation, the recommended leak inspection interval, and the manufacturer's leak rate threshold for triggering corrective action
+
+```datasheet
+label: Refrigerant Management Documentation
+type: checkbox
+options:
+ - "Refrigerant type and charge weight recorded on chiller nameplate"
+ - "Refrigerant data sheet (SDS) provided in O&M manual"
+ - "Initial leak inspection record at startup"
+ - "Recommended leak inspection schedule"
+ - "Refrigerant recovery and recycling plan for service events"
+default: "Refrigerant type and charge weight recorded on chiller nameplate"
+```
+
+# Delivery, Storage, and Handling
+
+Chillers shall be shipped in the manufacturer's standard shipping configuration with all openings sealed with manufacturer-supplied protective covers, the refrigerant circuit either charged or under a nitrogen holding charge, and the water sides either dry or with a corrosion inhibitor. The Contractor shall inspect packaging upon delivery for damage, photograph any damage, and notify the manufacturer before accepting the shipment.
+
+```datasheet
+label: Storage Conditions
+type: radio
+options:
+ - "Standard — indoor or covered, dry, less than 3 months until startup"
+ - "Extended — manufacturer's preservation protocol applied, 3 to 6 months"
+ - "Long-term — climate-controlled storage with periodic preservation activity, over 6 months"
+default: "Standard — indoor or covered, dry, less than 3 months until startup"
+```
+
+Where storage will exceed three months before startup, the manufacturer's long-term storage procedure shall be followed. This typically includes maintaining the nitrogen holding charge above atmospheric pressure (to prevent moisture ingress), rotating the compressor by hand at the manufacturer's specified interval, energizing oil heaters where the compressor is in a humid environment, and periodically replacing desiccant in the refrigerant circuit.
+
+Rigging and lifting shall use only the manufacturer's designated lift points. Lifting by piping connections, by the control panel, or by improperly placed straps risks damaging the casing, distorting the shells, or unbalancing the rigged load. The manufacturer's rigging diagram shall be available at the rigging location and shall be reviewed before any rigging activity.
+
+# Warranty
+
+```datasheet
+label: Warranty Period
+type: select
+options:
+ - "1 year parts and labor from startup (standard manufacturer warranty)"
+ - "1 year parts and labor + 4 additional years on compressor (5-year compressor)"
+ - "2 years parts and labor"
+ - "5 years parts and labor (extended, premium service)"
+default: "1 year parts and labor + 4 additional years on compressor (5-year compressor)"
+```
+
+The warranty shall cover defects in materials and workmanship under normal use and service conditions for the specified period. Standard manufacturer warranty for chillers is one year parts and labor with an additional four years on the compressor (frequently described as "1+4" or "5-year compressor"); this reflects the relative cost and complexity of compressor repair compared to other components. Extended warranties to two, three, or five years on the complete chiller are available at additional cost and may be justified for critical installations.
+
+Warranty shall not apply to damage caused by: operation outside the design conditions, operation with water chemistry outside the limits established by [[syncs/hvac-water-treatment]], operation without functional flow switches or freeze protection, lack of the manufacturer's specified annual maintenance, field-installed refrigerant of incorrect type or quality, or installation contrary to the manufacturer's published installation instructions.
+
+```datasheet
+label: Extended Warranty Coverage
+type: checkbox
+options:
+ - "Parts only beyond standard period"
+ - "Parts and labor beyond standard period"
+ - "Compressor only extended warranty"
+ - "Refrigerant included in warranty (replacement charge after repair)"
+ - "Annual preventive maintenance visit by manufacturer-authorized service"
+ - "Vibration analysis and oil analysis program"
+default: "Parts only beyond standard period"
+```
+
+# Spare Parts
+
+Spare parts shall be provided at substantial completion as follows. Spare parts shall be packaged for long-term storage and clearly labeled with the chiller tag, model, and serial number.
+
+```datasheet
+label: Spare Parts Required
+type: checkbox
+options:
+ - "One complete set of filter-driers per chiller"
+ - "One spare oil filter per chiller"
+ - "One set of refrigerant gaskets and o-rings per chiller"
+ - "One spare set of compressor contactors and overloads (across-the-line starters)"
+ - "One spare condenser fan motor (air-cooled, per fan size used)"
+ - "One spare control board (where chiller is critical and lead time is long)"
+ - "Manufacturer-recommended consumables for the first year of operation"
+default: "One complete set of filter-driers per chiller"
+```
+
+Filter-driers, oil filters, and gaskets are routine maintenance consumables that shall be on hand for the first scheduled service. A spare condenser fan motor is justified for air-cooled chillers because a fan motor failure can substantially reduce capacity until the motor is replaced and fan motors are sometimes long-lead items. A spare control board is justified only for critical installations because the boards are expensive and prone to fail individually rather than predictably across a fleet.
+
+```datasheet
+label: Maintenance Tools and Documentation
+type: checkbox
+options:
+ - "Manufacturer's installation, operation, and maintenance manual"
+ - "Refrigerant recovery and charging procedure specific to the unit"
+ - "Recommended preventive maintenance schedule"
+ - "Oil sampling instructions and recommended laboratory"
+ - "Tube cleaning procedure (water-cooled)"
+ - "Coil cleaning procedure (air-cooled)"
+ - "Spare parts ordering guide with manufacturer part numbers"
+default: "Manufacturer's installation, operation, and maintenance manual"
+```