1 Scope
NOTE This standard covers self-contained packaged terminal air conditioners (PTAC) and packaged terminal heat pumps (PTHP) installed through an exterior wall, each serving a single room or dwelling unit with independent zone control. (1.1)
NOTE A PTAC integrates a refrigeration circuit, an indoor fan coil, an outdoor condenser coil, and an electric resistance heating module in one chassis, providing mechanical cooling and resistance heating only. A PTHP adds a reversing valve so the same refrigeration circuit delivers reverse-cycle heating, with electric resistance heat acting as supplemental and emergency backup. Both types are air-source and reject or absorb heat directly to and from outdoor air through the exterior wall; neither uses chilled water, hot water, or a condenser water loop. (1.2)
NOTE The standard addresses chassis selection, wall sleeve and grille coordination, electrical service and branch-circuit provisions, supplemental resistance heat, fresh-air ventilation, condensate disposal, control interfaces, refrigerant selection, and energy-code compliance for both new construction and replacement of existing units. (1.3)
1.4Equipment furnished under this standard shall be a complete, factory-assembled, and factory-tested PTAC or PTHP package, ready for installation in a wall sleeve with field connection of a single dedicated branch circuit.
1.5Each unit shall serve one independently controlled zone.
1.6A single PTAC or PTHP shall not be ducted or manifolded to serve multiple rooms.
NOTE Fan-coil units served by a central chilled-water or hot-water plant are excluded and are covered by
Fan Coil Units.
(1.8) NOTE Heating-only unit heaters with no cooling function are excluded and are covered by
Unit Heaters.
(1.9) NOTE Water-source heat pumps that reject heat to a central condenser water loop are excluded and are covered by
Water Source Heat Pumps; PTAC and PTHP equipment is air-source only.
(1.10) NOTE The fire damper or combination fire/smoke damper within the through-wall penetration, where required by the building's fire-resistance rating, is excluded and is covered by
Fire And Smoke Dampers; the sleeve and grille opening shall be coordinated with that standard.
(1.11) NOTE Central air-handling units, rooftop units, and packaged DX equipment serving ducted distribution are outside the scope of this standard. (1.12)
NOTE Service-entrance and distribution equipment upstream of the unit branch circuit is excluded and is covered by
Electrical Service Entrance.
(1.13) 2 Referenced Standards
2.1Equipment, materials, and installation shall comply with the latest adopted edition of each of the following unless a specific edition is cited.
2.2Where referenced standards conflict, the more stringent requirement shall govern unless the Engineer of Record directs otherwise in writing.
| Standard |
Title |
| UL 60335-2-40 |
Household and Similar Electrical Appliances — Safety — Part 2-40: Particular Requirements for Electrical Heat Pumps, Air-Conditioners and Dehumidifiers |
| ANSI/AHRI 310/380 |
Standard for Packaged Terminal Air-Conditioners and Heat Pumps |
| ASHRAE 16 |
Method of Testing for Rating Room Air Conditioners and Packaged Terminal Air Conditioners |
| ASHRAE 90.1 |
Energy Standard for Sites and Buildings Except Low-Rise Residential Buildings (Table 6.8.1) |
| ASHRAE 62.1 |
Ventilation for Acceptable Indoor Air Quality |
| 10 CFR Part 431, Subpart F |
Energy Conservation Standards for Packaged Terminal Air Conditioners and Packaged Terminal Heat Pumps |
| NFPA 70 (NEC) |
National Electrical Code (Article 440, Air-Conditioning and Refrigerating Equipment) |
NOTE UL 1995 was formally retired on January 1, 2025 and replaced by UL 60335-2-40 as the primary North American safety and listing standard for this equipment; specification language that still references UL 1995 is outdated and shall not be used. (2.3)
NOTE DOE 10 CFR Part 431, Subpart F is the binding federal minimum-efficiency floor and compliance is mandatory. ASHRAE 90.1 Table 6.8.1 typically tracks the federal minimums but may be more stringent where a jurisdiction has adopted a recent edition; the more stringent of the two applies. (2.4)
3 Submittals
3.1 Action Submittals
3.1.1The Contractor shall submit the following action submittals for review before ordering equipment:
- Product data for each PTAC or PTHP model, including rated cooling and heating capacity, EER, COPH, electrical characteristics, sound ratings, and refrigerant type
- A unit schedule cross-referencing each room or unit number to its chassis model, capacity, voltage, resistance-heat kW, and sleeve size
- Wall sleeve and grille product data, including sleeve dimensions, depth, material, finish, and exterior louver style
- Wiring diagrams showing branch-circuit ampacity, minimum circuit ampacity (MCA), maximum overcurrent protection (MOCP), and disconnecting means
- Control interface description, including thermostat type and any energy management system (EMS) or BACnet/Modbus connection details
- Manufacturer's installation, operation, and maintenance (IOM) literature
☐ Product data (capacity, EER/COPH, electrical, sound, refrigerant)
☐ Unit schedule (room-to-chassis cross-reference)
☐ Wall sleeve and grille product data
☐ Wiring diagrams (MCA, MOCP, disconnect)
☐ Control interface / EMS connectivity description
☐ Manufacturer IOM literature
3.2.1The Contractor shall submit the following informational submittals:
- Manufacturer's AHRI 310/380 certified rating data or AHRI directory listing for each model
- UL 60335-2-40 listing mark and listing report reference
- Sound-pressure ratings (dB(A)) at low, high, and maximum fan speed
- Refrigerant type, charge weight, and A2L handling documentation where the refrigerant is classified A2L
☐ AHRI 310/380 certified ratings
☐ UL 60335-2-40 listing report
☐ Sound-pressure ratings at each fan speed
☐ Refrigerant type, charge, and A2L documentation
3.3 Closeout Submittals
3.3.1The Contractor shall submit the following closeout submittals before final acceptance:
- Completed manufacturer field startup checklist for each installed unit
- Operation and maintenance manuals
- Written warranty documents
- Record schedule of installed chassis and sleeve models by room
☐ Completed field startup checklists
☐ Operation and maintenance manuals
☐ Written warranty documents
☐ Record schedule of installed units by room
4 Quality Assurance
NOTE Equipment shall be the product of a manufacturer regularly engaged in the production of packaged terminal air conditioners and heat pumps for commercial hospitality and multifamily applications. (4.1)
4.2Each PTAC and PTHP chassis shall be listed to UL 60335-2-40.
4.3Each PTAC and PTHP chassis shall bear the listing mark of a Nationally Recognized Testing Laboratory.
4.4Each model shall be rated in accordance with ANSI/AHRI 310/380 and shall be listed in the AHRI directory.
4.5Cooling capacity and EER shall be established by test in accordance with ASHRAE 16 as referenced by AHRI 310/380.
4.6All chassis furnished for a single project shall be the product of one manufacturer to maintain interchangeability of parts and a consistent control interface.
4.7The Contractor shall verify the building electrical service voltage with the Electrical Engineer of Record before finalizing the unit schedule.
5.1 Mode of Operation
NOTE The selected mode of operation shall match the heating strategy for the project's climate. A PTAC provides mechanical cooling and electric resistance heating only; it has no heat-pump heating and provides no heating at all unless a resistance heat module is furnished. A PTHP provides reverse-cycle heat-pump heating that is far more efficient at moderate outdoor temperatures, with resistance heat used only as supplemental and emergency backup at low outdoor temperatures. (5.1.1)
NOTE Specifying a PTAC without a resistance heat module in any climate that requires heating leaves the room with no heat source; the heating method and, for resistance heat, its kW rating shall be explicitly stated and never left blank. (5.1.2)
○ PTAC (cooling + electric resistance heat)
● PTHP (heat pump + electric resistance backup heat)
○ PTHP (heat pump, no supplemental resistance heat)
5.2 Cooling Capacity
NOTE Cooling capacity shall be selected from a room-by-room load calculation, not from floor area alone. For exposed corner rooms, rooms with high glazing ratios, and rooms with elevated occupancy density, the load shall be established by a Manual N or equivalent ASHRAE cooling-load analysis. (5.2.1)
5.2.2Each unit shall be sized to meet the calculated room cooling load at the AHRI 310/380 rating condition of 95°F outdoor dry bulb and 80°F/67°F indoor dry-bulb/wet-bulb.
NOTE Standard-size chassis between 7,000 and 15,000 BTU/h cover the great majority of hotel and multifamily rooms; a typical 200 to 400 SF room falls in the 9,000 to 12,000 BTU/h range. (5.2.3)
7000
9000
9300
12000
14000
15000
5.3 Minimum Efficiency
5.3.1Each unit shall meet or exceed the minimum efficiency required by DOE 10 CFR Part 431, Subpart F, and by ASHRAE 90.1 Table 6.8.1 as adopted by the jurisdiction, whichever is more stringent.
NOTE For standard-size cooling capacity between 7,000 and 15,000 BTU/h, the minimum cooling efficiency is EER ≥ 14.0 − (0.300 × Cap/1000), where Cap is the rated cooling capacity in BTU/h. For example, a 12,000 BTU/h unit shall provide EER ≥ 10.4. Units below 7,000 BTU/h shall provide EER ≥ 11.9; units above 15,000 BTU/h shall provide EER ≥ 9.3. (5.3.2)
NOTE For PTHP equipment, the minimum heating efficiency at 47°F outdoor dry bulb is COPH ≥ 3.2 for standard-size units of 7,000 to 15,000 BTU/h, COPH ≥ 3.3 for units below 7,000 BTU/h, and COPH ≥ 2.9 for units above 15,000 BTU/h, all measured per AHRI 310/380. (5.3.3)
5.3.4The scheduled EER, and the scheduled COPH for PTHP units, shall be the AHRI 310/380 certified rating and shall meet or exceed the applicable minimum.
5.4 Supplemental Resistance Heat
5.4.1Supplemental electric resistance heat shall be furnished where the heating load cannot be met by the heat pump alone at the design outdoor temperature, or where a PTAC is selected and resistance heat is the sole heat source.
5.4.2Resistance heat for a PTHP shall be controlled to operate only as supplemental and emergency backup.
5.4.3Resistance heat for a PTHP shall not run simultaneously with the compressor heating mode except during defrost.
NOTE The 80% case for a standard hotel room is a 3.5 kW resistance heat module; mild southern climates may require no supplemental heat, and high-load or all-resistance applications may require 5.0 kW. (5.4.4)
○ None (mild climate, heat pump only)
○ 2.5 kW
● 3.5 kW
○ 5.0 kW
5.5 Sound Ratings
NOTE PTAC and PTHP units installed in guest rooms and dwelling units shall meet a published low-fan-speed sound-pressure level not exceeding the value scheduled for the project; for typical hotel applications a target of ≤ 45 dB(A) at low fan speed is recommended. (5.5.1)
5.5.2The scheduled sound rating shall be the manufacturer's published A-weighted sound-pressure level at the corresponding fan speed; sound ratings shall not be omitted from the schedule.
5.6 Refrigerant
5.6.1The refrigerant type shall be specified in the unit schedule.
5.6.2Where an A2L lower-GWP refrigerant is selected, the chassis shall be listed to UL 60335-2-40 for that refrigerant class and the manufacturer's A2L handling and charge-limit requirements shall be observed.
5.6.3For new construction, R-32 or another A2L lower-GWP refrigerant should be specified to align with the DOE transition timeline.
NOTE Units ordered with R-410A may face rising servicing cost as the AIM Act phase-down tightens supply. (5.6.4)
6 Electrical Service
6.1 Service Voltage
NOTE The chassis electrical characteristics shall match the building's branch-circuit voltage. Specifying a 208/230 V chassis for a building wired at 265 V, or the reverse, is a common and avoidable RFI; the service voltage shall be confirmed with the Electrical Engineer of Record before the schedule is finalized. (6.1.1)
NOTE The most common service is 208/230 V, single phase, 60 Hz. A 265 V chassis is available for legacy high-rise hotels wired at 265 V. A 120 V chassis is limited to residential-grade units below 9,000 BTU/h. (6.1.2)
● 208/230 V, 1Φ, 60 Hz
○ 265 V, 1Φ, 60 Hz
○ 120 V, 1Φ, 60 Hz (units < 9,000 BTU/h only)
6.2 Branch Circuit and Overcurrent Protection
6.2.1Each unit shall be served by a dedicated branch circuit sized in accordance with NEC Article 440 at not less than 125% of the unit's minimum circuit ampacity (MCA) marked on the data plate.
6.2.2The branch-circuit overcurrent device shall not exceed the maximum overcurrent protection (MOCP) marked on the unit data plate.
6.2.3A disconnecting means shall be provided for each unit in accordance with NEC Article 440, located within sight of the unit or capable of being locked open.
6.2.4Each unit and its branch circuit shall be grounded in accordance with NEC Article 250.
NOTE Branch circuits for PTAC and PTHP units are typically 20 A or 30 A; the rating shall be selected to match the unit MCA and shall never exceed the unit MOCP. (6.2.5)
7 Wall Sleeve and Grille
7.1 Sleeve Selection and Compatibility
NOTE PTAC chassis and sleeves are not dimensionally universal across manufacturers; for example, common sleeve widths differ by brand. For replacement work, the existing sleeve brand and interior dimensions shall be verified before a replacement chassis is selected, or a universal-fit retrofit chassis shall be specified. (7.1.1)
NOTE For new construction the wall sleeve shall be the industry-standard 42 in. wide × 16 in. high opening with an integral rear louver, unless a non-standard size is required by the existing wall condition. (7.1.2)
7.1.3The wall sleeve shall be galvanized or otherwise corrosion-resistant steel and shall be sized for the selected chassis with the manufacturer's required clearances.
NOTE Sleeve depth shall match the wall construction thickness, typically 13 to 16 in., so that the exterior grille sits flush with the finished exterior face. (7.1.4)
● Standard 42 in. W × 16 in. H
○ Non-standard / legacy size (verify field dimensions)
NOTE For replacement projects within a portfolio of mixed legacy sleeves, a universal-fit retrofit chassis sized to the existing sleeve opening should be specified to avoid sleeve replacement and brand lock-in. (7.1.5)
● Brand-matched chassis (new sleeve)
○ Universal-fit retrofit chassis (existing sleeve)
7.2 Exterior Grille and Interior Cover
7.2.1The exterior grille or louver style shall be coordinated with the building facade and shall be one of the architectural or institutional styles specified.
7.2.2An interior decorative cover panel shall be furnished where the chassis face is exposed within the occupied room; the finish shall be as scheduled.
NOTE The grille and sleeve opening shall be coordinated with the fire/smoke damper requirements of
Fire And Smoke Dampers where the wall carries a fire-resistance rating.
(7.2.3) ● Architectural aluminum louver
○ Institutional steel grille
Manufacturer standard neutral
Custom color to match room
7.3 Structural Coordination
NOTE A through-wall sleeve penetration in masonry, concrete masonry unit, or concrete wall construction requires a structural lintel or header above the opening; the opening and its support shall be coordinated with the structural drawings. (7.3.1)
7.3.2The sleeve opening location, size, and required lintel or header shall be shown on the drawings. sleeve opening and lintel 8 Ventilation and Fresh Air
NOTE The fresh-air provision shall satisfy the minimum outdoor-air ventilation rate required by ASHRAE 62.1 for the occupancy, typically 15 to 20 CFM per person for single-occupancy hotel and dwelling rooms. (8.1)
NOTE A fixed-open fresh-air damper fails ASHRAE 90.1 and equivalent state energy codes in many jurisdictions because it admits unconditioned outdoor air continuously; a motorized auto-close damper coordinated with the room control sequence is the 80% case for energy compliance. (8.2)
8.3The fresh-air damper type shall be coordinated with the adopted energy code and with the room occupancy control sequence so that outdoor air is admitted only when required and the damper closes on unoccupied setback.
NOTE Where the project ventilation strategy requires more outdoor air than a damper can provide, a unit with an integrated fresh-air or dedicated-outdoor-air module may be specified to meet ASHRAE 62.1 without a separate energy-recovery ventilator. (8.4)
● Motorized auto-close damper
○ Manually adjustable damper
○ Fixed-open damper
○ Sealed (no fresh air)
9 Condensate Disposal
NOTE The wall sleeve shall slope toward the exterior by not less than 1/4 in. total so that condensate drains away from the room; a sleeve installed level or sloped inward causes water intrusion, staining, and mold and shall not be accepted. (9.1)
9.2The sleeve shall be set with a positive slope of not less than 1/4 in. toward the exterior face.
NOTE The condensate disposal method shall be selected to match the installation: gravity drain to the exterior through the sloped sleeve is standard; a condensate evaporator (slinger) chassis eliminates the exterior drip where it is objectionable; and a condensate pump may be used where an internal drain connection is required. (9.3)
● Gravity drain to exterior via sloped sleeve
○ Condensate evaporator (no exterior drain)
○ Condensate pump to internal drain
10 Controls
NOTE The control interface shall be coordinated with the building's room-control strategy. Hotel energy management systems commonly use proprietary protocols; specifying a chassis without a compatible control interface results in stand-alone operation with no occupancy-based setback. (10.1)
10.2Where the project uses a centralized energy management system or building automation system, the unit shall be furnished with a control interface compatible with that system, including any required PTAC interface (PTI) accessory or BACnet/Modbus connectivity.
10.3Each unit shall include an integral room temperature control with a setpoint and fan-speed selection accessible to the occupant unless the project requires lockout to a central system.
10.4Occupancy-based setback, where required, shall be coordinated with the room occupancy sensing and the EMS so that unoccupied rooms revert to an energy-saving setpoint.
○ Integral manual thermostat
● Integral digital display thermostat
○ Centralized EMS interface (PTI)
○ BACnet / Modbus connectivity
11 Testing
11.1Each unit shall be factory tested in accordance with ANSI/AHRI 310/380 at the manufacturer's facility prior to shipment.
11.2The Contractor shall perform a field startup of each installed unit in accordance with the manufacturer's IOM, including verification of refrigerant operation, heating operation, condensate drainage, fresh-air damper operation, and control response.
11.3A completed field startup checklist shall be furnished for each unit before the room is released for occupancy.
11.4Any unit failing to achieve its scheduled cooling or heating performance at startup shall be corrected or replaced at no additional cost to the Owner.
12 Installation
12.1Units shall be installed in accordance with the manufacturer's IOM, the approved submittals, and the requirements of this standard.
12.2The wall sleeve shall be installed plumb and level except for the required 1/4 in. exterior slope.
12.3The wall sleeve shall be sealed to the wall opening to prevent air and water infiltration around the sleeve.
12.4The branch circuit, disconnecting means, and grounding shall be completed and inspected before the chassis is energized.
12.5The chassis shall be inserted into the sleeve only after the sleeve, drainage slope, and electrical service have been verified complete.
12.6Interior cover panels and exterior grilles shall be installed without distortion and shall seat fully to the sleeve.
12.7The fresh-air damper shall be set and its control connection verified during installation so that the as-built damper position matches the energy-compliance basis of design.
13 Delivery, Storage, and Handling
13.1Units shall be delivered in the manufacturer's original packaging with the chassis and sleeve identified for the room each serves.
13.2Units shall be stored upright, indoors, protected from weather, moisture, dust, and physical damage until installation.
13.3Chassis containing charged refrigeration circuits shall be handled and stored within the temperature and orientation limits stated in the manufacturer's IOM.
13.4Damaged units, sleeves, or grilles shall be replaced and shall not be repaired in the field without the manufacturer's written approval.
14 Warranty
14.1The manufacturer shall warrant each PTAC and PTHP unit against defects in materials and workmanship for not less than the manufacturer's standard warranty period from the date of substantial completion.
14.2The sealed refrigeration circuit, including the compressor, shall carry the manufacturer's extended sealed-system warranty.
14.3Warranty documents shall be submitted as a closeout submittal and shall identify the start date, duration, and coverage for each warranted component.
15 Spare Parts
15.1The Contractor shall furnish the manufacturer's recommended quantity of spare air filters for the installed units.
NOTE Where a single chassis model serves a large number of rooms, the Owner should procure spare complete chassis sufficient to maintain service continuity during warranty replacement. (15.2)
15.3A schedule of recommended spare parts, with manufacturer part numbers, shall be provided in the operation and maintenance manuals.