YORK P Series Wall-Mounted Heat Pump 18 SEER | 12000 BTU 220V

A YORK P Series 12,000 BTU wall-mounted heat pump designed for simple, precise, and efficient control of a zone

The YORK P Series 12,000 BTU 220 V wall-mounted heat pump uses a simple mini-split configuration: a wall-mounted indoor unit DHP12NWB21S paired with an outdoor unit DHP12CSB21S. This is a single-zone system with an Inverter-technology compressor, designed for both heating and cooling a room or clearly defined area.

For a homeowner in Montreal, Laval, Longueuil, the North Shore or the South Shore, the main advantage of this configuration is its simplicity. It requires no ductwork and can directly serve an area with a specific need: a living room, open-concept area, floor, office, addition, apartment, or section of a house where the existing heating system does not distribute the temperature evenly.

The YORK catalog classifies the P Series among systems capable of reaching up to 18 SEER. However, an important technical clarification is needed for the reference presented here: the exact combination DHP12NWB21S + DHP12CSB21S, identified by AHRI number 8578541, is listed by YORK at 16 SEER, not 18 SEER. The manufacturer's catalog also confirms that the 12,000 BTU 208/230 V version delivers 12,000 BTU/h in cooling and 13,000 BTU/h nominally in heating.

This distinction is important at AirGreen: the name of a series and the certified performance of a specific combination are not always identical. We therefore prefer to work with the complete model number and AHRI number rather than with a commercial name taken in isolation.

Key specifications

For the YORK DHP12NWB21S / DHP12CSB21S combination, the manufacturer's data provides a much more precise picture than simply stating “12,000 BTU”:

• Type: single-zone, wall-mounted mini-split heat pump, Inverter
• Indoor unit: DHP12NWB21S
• Outdoor unit: DHP12CSB21S
• AHRI number: 8578541
• Nominal cooling capacity: 12,000 BTU/h
• Cooling modulation range: approximately 3,753 to 12,500 BTU/h
• Nominal heating capacity: 13,000 BTU/h
• Heating modulation range: approximately 3,924 to 14,000 BTU/h
• Certified efficiency of this combination: 16 SEER, HSPF 9
• Power supply: 208/230 V, single-phase, 60 Hz
• MCA: 9 A
• MOCP/MOP: 15 A
• Refrigerant: R-410A
• Refrigerant piping: 1/4 in liquid line, 3/8 in gas line
• Maximum piping length: approximately 65 ft
• Maximum height difference: approximately 33 ft
• Indoor airflow: approximately 194 to 400 CFM, depending on speed
• Indoor sound pressure: approximately 29 to 43 dB(A), depending on speed
• Outdoor sound pressure: approximately 53 dB(A)
• Indoor dimensions listed in the catalog: approximately 33 × 11 × 8 in
• Outdoor dimensions: approximately 30.5 × 21 × 12.5 in
• Wi-Fi: optional with a compatible adapter
• Wireless remote control: included according to YORK documentation
• Heating operation: down to approximately -20 °C, according to the manufacturer's operating range

The dimensions, electrical data, sound levels, refrigerant connections, and piping limits for this combination are detailed in the YORK technical table.

Why the 18 SEER designation deserves an explanation

The term “18 SEER P Series” refers to the product family as it was marketed, with P Series configurations capable of reaching 18 SEER. However, the 12,000 BTU combination covered by this page is certified at 16 SEER under AHRI 8578541. YORK still explicitly lists it as a 1-ton, 16 SEER P Series heat pump.

It is also important to avoid automatically mixing up SEER and SEER2. This YORK generation was evaluated using the former SEER/HSPF certification methods. A SEER2 value should therefore not be invented by mathematically converting the original SEER. To compare this system with a current wall-mounted heat pump, we instead recommend comparing the complete AHRI directories and low-temperature capacities.

This approach avoids an error we regularly see in the HVAC industry in Montreal and Greater Montreal: comparing two heat pumps solely because their nominal capacity is 12,000 BTU, even though their modulation, winter efficiency, certification, and low-temperature performance may be very different.

Heating down to -20 °C: what this figure really means

The YORK catalogue indicates a heating operating range down to -20 °C for this P Series. It is essential to understand that this is a minimum operating temperature, not a guarantee that the unit will still provide its nominal 13,000 BTU when the outdoor temperature reaches -20 °C.

The nominal heating capacity of 13,000 BTU is determined under much milder standardized conditions. As with all heat pumps, available capacity and efficiency vary with outdoor temperature.

In the climate of Montréal, Laval, Longueuil, the North Shore, and the South Shore, this distinction directly affects sizing. A heat pump capable of continuing to operate at -20 °C is not automatically sized to replace all of a home’s heating on its own during a period of intense cold.

At AirGreen, we therefore consider the building as a whole: insulation, windows, orientation, zone area, ceiling height, air infiltration, and the presence of supplemental heating.

More comfortable Inverter modulation than start-stop operation

The variable-speed compressor is one of the key elements of this P Series. Rather than operating only at full capacity and then shutting off, the unit can adjust its output to match demand.

In this 12,000 BTU configuration, YORK indicates modulation in cooling mode of approximately 3,753 to 12,500 BTU/h and in heating mode of approximately 3,924 to 14,000 BTU/h.

In a properly sized room, this modulation helps limit short cycles. The unit can maintain a stable temperature for longer with an airflow suited to the actual load.

This is particularly relevant in a condo or open area where an oversized system could cool the room very quickly, shut off, and then restart frequently. The comfort of a wall-mounted heat pump therefore depends as much on proper sizing as on its maximum capacity.

Automatic vertical and horizontal louvers: a real advantage for air distribution

The P Series offers more comprehensive louver control than several simpler wall-mounted units. The YORK feature chart lists 3D Auto Swing for the P Series, meaning automatic vertical and horizontal oscillation, in addition to up-and-down, left-to-right movements and fixed-angle positions.

This helps distribute the air more evenly in an open area instead of concentrating the airflow directly in front of the evaporator.

For an AirGreen installation, the indoor unit is positioned specifically with this airflow in mind. Whenever possible, we avoid placing the unit where its air stream will be immediately blocked by a tall cabinet, beam, cross wall, or large piece of furniture.

In cooling mode, properly directed airflow helps cool air move throughout the room. In heating mode, louver positioning affects how warm air reaches the occupied area rather than remaining near the ceiling.

Airflow and sound level

The YORK catalog lists four airflow levels for the DHP12NWB21S, ranging from approximately 194 to 400 CFM. Indoor sound pressure levels drop to approximately 29 dB(A) at low speed and rise to approximately 43 dB(A) at the highest setting.

This makes this heat pump an interesting option for a living room, office, or bedroom when the 12,000 BTU capacity truly matches the room's load.

Maximum airflow is still important, however. A quiet heat pump installed in the wrong location can become less comfortable if it has to constantly operate at high speed to push air toward a distant part of the room. Location selection is therefore an integral part of perceived acoustic performance.

Optional Wi-Fi and YORK remote control

The DRCPX wireless remote is associated with the P and X Series in YORK documentation. For phone control, YORK indicates that the P and X Series can use the EWPE Smart App with the CS532AH adapter.

Wi-Fi is therefore not a feature we automatically consider integrated into this generation of the P Series. It is an option requiring the appropriate adapter.

For an older installation where the owner wants to add remote control, exact compatibility must also be confirmed before ordering the accessory. The indoor unit reference is more reliable than its exterior appearance for choosing the right controller.

Installation of the YORK P Series in Montreal, Laval, Longueuil, the North Shore, and the South Shore: the details that make the difference

The 12,000 BTU capacity should not be chosen solely based on floor area

A rough square-footage rule can be useful for an initial discussion, but it is not enough to properly select a 12,000 BTU heat pump.

Two rooms of identical dimensions can have very different heating and cooling loads. A very open, heavily windowed space facing due south in Longueuil may require a different approach from a room of the same size located in the center of a building in Montreal.

We examine the insulation, windows, sun exposure, number of exterior walls, floor level, ceiling height, and connections between rooms.

An undersized unit will often operate at high capacity. An oversized unit may reach the requested temperature too quickly without providing the same control of humidity and temperature throughout the area.

A scenario in which this configuration may be suitable

Consider an open-concept area that already has a functioning electric heating system but becomes uncomfortably hot in the summer. The homeowner wants to add air conditioning while also benefiting from heat pump heating during a significant part of the winter.

In this type of situation, we first check whether 12,000 BTU match the actual load. We then determine a wall that allows air to circulate through as much of the space as possible. Outdoors, we look for an accessible location for maintenance while respecting the required clearances.

The result depends much less on the brand shown on the front than on the quality of the sizing, refrigeration line routing, drainage, evacuation, and commissioning.

A proper installation involves much more than two units mounted on the wall

For a typical YORK wall-mounted heat pump installation, our work includes several technical steps:

1. Capacity validation based on the building and the area to be conditioned.
2. Selection of indoor and outdoor locations, taking into account air distribution, noise, future maintenance, and drainage.
3. Installation of 1/4 in – 3/8 in piping, in accordance with the connections for this combination.
4. 208/230 V electrical connection with protection suited to the manufacturer's MCA/MOCP requirements.
5. Evacuation and vacuuming of the refrigeration circuit, followed by leak testing and commissioning.
6. Heating and cooling test, inspection of the drainage, louvers, and fan speeds, and explanation of the controls to the homeowner.

For this model, the manufacturer specifies an MCA of 9 A and a maximum protection of 15 A. This does not mean that an installer can simply rely on an existing circuit because it already has a 15 A circuit breaker. The cable type, circuit, outdoor disconnect, and compliance of the electrical installation must also be verified.

The 1/4 in. – 3/8 in. piping must be respected

The DHP12NWB21S / DHP12CSB21S combination uses a 1/4 in. liquid line and a 3/8 in. gas line. YORK indicates a maximum total length of approximately 65 ft and a maximum height difference of approximately 33 ft for this configuration.

These details become particularly important when a heat pump is replacing an older unit.

Automatically reusing existing lines without checking their diameter, condition, previous refrigerant, and the new equipment’s requirements is poor practice. Even if two systems are both rated at 12,000 BTU, their connections are not necessarily identical.

Drainage remains a frequent source of preventable problems

A wall-mounted heat pump removes moisture from the air in cooling mode. The water must be properly discharged through the condensate drain.

A drain that is improperly sloped, crushed, or incorrectly connected can eventually cause indoor leaks. Filter and evaporator maintenance also play a role: a heavily soiled unit can reduce airflow and interfere with the system’s normal operation.

For an older unit like this P Series generation, preventive maintenance is even more important. We check, among other things, the cleanliness of the evaporator, the blower wheel, the drain pan, the outdoor coil, and visible connections.

Warranty: verify equipment registration

YORK documentation for this generation mentions a standard warranty of 7 years on the compressor and 5 years on parts, with the possibility of extending it to 10 years on the compressor and 10 years on parts after eligible registration of a residential installation.

The AirGreen listing for this configuration, for its part, shows 10-10-0 years: 10 years for the compressor, 10 years for parts, and no manufacturer’s labor warranty included.

For a unit from existing stock, we recommend always confirming the conditions applicable to the specific serial number, the installation date, and the registration requirements. AirGreen can also explain the additional warranty options available at the time of quotation.

LogisVert: this reference is not a current eligible ENERGY STAR model

The specifications for this YORK P Series indicate ENERGY STAR: No and ENERGY STAR – Cold Climate: No.

This point has a direct consequence for an installation carried out today. Hydro-Québec specifies that heat pumps installed as of November 26, 2025, must be ENERGY STAR certified to be eligible for the LogisVert program.

The YORK DHP12NWB21S / DHP12CSB21S should therefore not be presented as a heat pump currently eligible for the LogisVert subsidy simply because it offers 12,000 BTU or because it can operate down to -20 °C.

For a homeowner whose priority is to benefit from a Hydro-Québec subsidy, we instead compare this option with current ENERGY STAR-certified heat pumps and, where relevant, ENERGY STAR – Cold Climate models. Hydro-Québec indicates, in particular, that assistance is linked to eligible cold-climate heat pumps based on their heating capacity at -8 °C.

For which project does this YORK P Series remain an interesting option?

This configuration retains practical features: Inverter technology, 12,000 BTU cooling capacity, heating, modulation, a remote control, automatic two-way louver control, and the option to add a compatible Wi-Fi control.

It may be of interest when a homeowner is specifically looking for this model, when it is suitable for a compatible replacement project, or when a unit in stock is available on attractive terms.

However, for a new heat pump installation in Montreal, Laval, Longueuil, on the North Shore or the South Shore, we recommend comparing its final cost with that of newer models offering ENERGY STAR certification, better cold-weather performance, and potential eligibility for financial assistance programs.

The purchase price alone does not determine the best choice. A less expensive heat pump that is not eligible for a subsidy may end up costing more than a higher-end model once the net cost is calculated.

Frequently asked questions about the YORK DHP12NWB21S / DHP12CSB21S

Does the 12,000 BTU YORK P Series really provide heating at -20 °C?

The manufacturer indicates a heating operating range down to approximately -20 °C. This temperature represents a published operating limit, not a guaranteed capacity of 13,000 BTU at -20 °C. Available capacity generally decreases as the outdoor temperature drops.

Is this heat pump really 18 SEER?

The P Series is marketed as a range of up to 18 SEER, but the specific combination DHP12NWB21S + DHP12CSB21S, AHRI 8578541, is certified at 16 SEER.

Are the horizontal and vertical louvers automatic?

Yes. YORK's function table lists 3D Auto Swing for the P Series, including automatic vertical and horizontal swing. It also lists up-and-down, left-and-right, and fixed-angle movement functions.

Is Wi-Fi included?

No. For this generation, YORK lists Wi-Fi as an option. The CS532AH adapter is required for the P Series to use the compatible phone-control function.

What piping should be used?

For the 12,000 BTU 208/230 V model presented here, the listed connections are 1/4 in. for liquid and 3/8 in. for gas.

Is this heat pump eligible for LogisVert?

For a current installation, not according to the information available for this combination. It is identified as non-ENERGY STAR, while Hydro-Québec requires ENERGY STAR certification for heat pumps installed since November 26, 2025, to qualify for the corresponding LogisVert measure.

Have your heat pump installed by AirGreen

At AirGreen Heat Pumps, Air Conditioning & Heating, we install and service HVAC systems throughout Greater Montreal, including Montreal, Laval, Longueuil, the South Shore, and the North Shore.

Our work does not simply consist of selecting a number of BTUs. We verify the required capacity, electrical supply, piping, drainage, clearances, airflow, and system compatibility with the homeowner's objectives.

For this YORK P Series model, as with a newer-generation wall-mounted heat pump, we can also compare the actual cost after rebates, winter performance, and warranties so that the choice remains suitable for many years after installation.

Contact AirGreen to obtain a quote, check the availability of the YORK DHP12NWB21S / DHP12CSB21S, or compare this unit with the ENERGY STAR wall-mounted heat pumps currently available in Montreal, Laval, Longueuil, on the North Shore and the South Shore.