YORK P Series Wall-Mounted Heat Pump 18 SEER | 18000 BTU

An 18,000 BTU YORK wall-mounted heat pump to evaluate using the right technical data

The 18,000 BTU YORK P Series wall-mounted heat pump is intended for homeowners seeking a ductless system capable of providing both cooling and heating for a significant area of the home. In Montreal, Laval, Longueuil, the North Shore, and the South Shore, this type of unit may be suitable for an open-concept floor, a large living room, an apartment, an office, or certain light commercial spaces, provided that it is properly sized for the building's actual load.

The system presented here combines the DHP18NWB21S indoor unit with the DHP18CSB21S outdoor unit. YORK documentation from 2020 confirms that this is indeed the 18,000 BTU P Series heat pump system powered by 208/230 V.

One point should be clarified from the outset. The name “P Series 18 SEER” refers to a YORK family advertised as offering up to 18 SEER. For the specific DHP18NWB21S / DHP18CSB21S combination, the official brochure indicates a rating of 16 SEER, not 18 SEER, as well as an EER of 9 and an HSPF of 9. This distinction is important when comparing this heat pump with newer units using the new SEER2 and HSPF2 ratings.

At AirGreen, we prefer to present this distinction clearly. A useful HVAC comparison must be based on the exact model's data, not just the series' commercial name.

Technical specifications for the DHP18CSB21S / DHP18NWB21S model

For the 18,000 BTU model, YORK documentation provides sufficiently detailed data to properly plan a wall-mounted heat pump installation:

• Rated cooling capacity: 18,000 BTU/h
• Cooling capacity range: 7,165 to 20,000 BTU/h
• Rated heating capacity: 19,000 BTU/h
• Heating capacity range: 7,336 to 23,498 BTU/h
• SEER: 16 for this specific model
• EER: 9
• HSPF: 9
• Power supply: 208/230 V, single-phase, 60 Hz
• MCA: 16 A
• MOCP / maximum overcurrent protection: 25 A
• Refrigerant: R-410A
• Cooling operating range: -18 °C to 46 °C
• Heating operating range: -20 °C to 24 °C
• Refrigerant piping: 1/4 in. liquid and 1/2 in. gas
• Maximum piping length: 82 ft, or approximately 25 m
• Maximum elevation difference: 33 ft, or approximately 10 m
• Indoor airflow: 471 / 403 / 341 / 282 CFM
• Indoor sound pressure: 46 / 42 / 39 / 35 dB(A)
• Outdoor sound pressure: 56 dB(A)
• Indoor unit dimensions: 38 × 12 × 9 in.
• Outdoor unit dimensions: 38 × 28 × 16 in.

Airflow, sound, dimensions, piping, and operating range values are all specified in the YORK technical table for the 9,000, 12,000, and 18,000 BTU models in the P Series.

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

The statement heating at -20 °C must be interpreted correctly. YORK indicates that the DHP18CSB21S can operate in heating mode down to an outdoor temperature of -20 °C. This does not mean that the unit necessarily produces its nominal 19,000 BTU/h when the outdoor temperature reaches -20 °C.

The brochure provides a nominal heating capacity of 19,000 BTU/h and a modulating range of 7,336 to 23,498 BTU/h, but it does not provide, in this table, the certified capacities at -8 °C, -15 °C, or -20 °C. We therefore avoid inventing a low-temperature output that the manufacturer has not published in this documentation.

This distinction is particularly important in Quebec. In Montreal, Laval, Longueuil, Boucherville, Terrebonne, Repentigny, or on the South Shore, a heat pump is not selected solely according to its nominal cooling capacity. We must also consider the building’s heating requirements, insulation, exposure to wind, heat loss through the windows, the area actually served, and the presence of supplemental heating.

Interesting modulation for everyday comfort

The Inverter technology compressor allows the unit to operate without relying solely on an on-off logic. Capacity can vary with demand, which helps maintain a more stable temperature and limits repeated cycles when the thermal load is low.

For the homeowner, this modulation is most noticeable during less demanding periods. A September day in Montreal does not require the same output as a heat wave in July. Similarly, maintaining a room at temperature in October does not require the same capacity as an evening in January.

It is precisely during these transitional periods that modulation can contribute to comfort. The goal of proper sizing is not to systematically choose the appliance displaying the highest BTU rating, but to select a capacity compatible with the zone’s actual thermal behavior.

Automatic louvers in both directions

The P Series has a particularly interesting feature for a wall-mounted unit: the YORK table lists 3D Auto Swing, meaning automatic vertical and horizontal oscillation. It also confirms the up-and-down and left-to-right swing functions, as well as fixed-angle positioning.

For the model sold by AirGreen, we therefore indicate:

Vertical louvers: automatic
Horizontal louvers: automatic

This feature is more important than it may seem. In a large rectangular living room, an open-concept area, or a space with an adjacent hallway, the direction of the airflow directly influences temperature uniformity. An 18,000 BTU unit installed in the wrong location may deliver less satisfactory results than a properly positioned and oriented appliance.

During our HVAC installations in Montreal, Laval, Longueuil, on the North Shore and the South Shore, we therefore examine not only the available wall space, but also the path of the air. Whenever possible, we avoid directing the airflow straight at a sofa, bed, or area where occupants spend extended periods.

Four genuinely documented airflow levels

For the DHP18NWB21S indoor unit, YORK specifies airflow rates of 471, 403, 341, and 282 CFM depending on the selected speed.

This variation makes it possible to prioritize either stronger airflow or quieter operation. The associated sound levels range from 46 dB(A) at high speed to 35 dB(A) at low speed.

This is useful information for a bedroom, but even more so for a living room or workspace. An appliance may have an appealing minimum rating while becoming noticeably more audible when it has to move a large volume of air. We therefore prefer to look at the entire sound range rather than a single promotional value.

The outdoor unit is rated at 56 dB(A). Its location should therefore be chosen carefully, particularly in neighborhoods where houses, condos, or plexes are close together. A poor location can transmit more noise toward a window, balcony, terrace, or neighboring property.

Optional Wi-Fi and standard wireless remote control

The P Series includes a DRCPX wireless remote control. For control via smartphone or tablet, Wi-Fi is not built into this model as standard: YORK indicates that the CS532AH adapter is required.

The controller documentation also specifies that the EWPE Smart app is compatible with the P, X, and Z Series, with a CS532AH adapter required for the P and X Series.

Therefore, two elements must be clearly distinguished:

Infrared remote control: included.
Wi-Fi control: optional with the appropriate accessory.

This is the kind of detail we verify before promising a connected feature to a customer. Two wall-mounted units that look very similar may have different electronic configurations.

Installation, performance, and selection of this YORK P Series in Greater Montreal

1/4 in. - 1/2 in. piping that must be followed

The DHP18NWB21S / DHP18CSB21S combination requires a liquid line of 1/4 po and a gas line of 1/2 po.

This information is particularly important when replacing an old heat pump. It may be tempting to automatically reuse the existing lines because they already pass through a finished wall. At AirGreen, we first check their diameter, condition, length, accessibility, and compatibility with the system.

A common example is a homeowner who wants to replace an old unit without redoing the exterior trim. If the existing piping is the wrong diameter or has contamination, a restriction, or a questionable connection, keeping that piping solely to reduce the work can compromise the operation of the new appliance.

For this YORK unit, the brochure allows up to 82 feet of total length and 33 feet of height difference. These limits provide some flexibility for multilevel homes, but they do not replace proper route planning.

A 208/230 V power supply with an MCA of 16 A

The 18,000 BTU P Series operates on 208/230 V single-phase power. The documentation specifies a minimum circuit ampacity of 16 A and maximum overcurrent protection of 25 A.

The 25 A MOCP value must not be interpreted as an invitation to modify the circuit breaker yourself. The circuit must be verified based on the installation, wiring, appliance requirements, and applicable electrical standards in Quebec.

In a replacement project in Montreal or Longueuil, for example, the presence of an existing 240 V circuit does not automatically guarantee that it is suitable for the new heat pump. We check the electrical specifications before installation to avoid improvised modifications on the day of the work.

Dimensions to check before choosing the wall

The indoor unit measures approximately 38 in wide, 12 in deep, and 9 in high. This 18,000 BTU size requires more width than a small 9,000 or 12,000 BTU wall-mounted unit.

We must also maintain the necessary clearances around the appliance so that air can be properly drawn in and distributed and the unit remains accessible for HVAC maintenance.

The outdoor unit measures approximately 38 × 28 × 16 in. Its location must account for airflow, snow, drainage during defrosting, service access, and the regulations applicable to the location.

On the South Shore and North Shore, installations in single-family homes sometimes offer more flexibility. In certain Montreal boroughs or in condominiums, space constraints, balconies, and administrative requirements may require more precise planning.

R-410A: a factor to consider for this model

This YORK P Series uses R-410A. This is an important characteristic to know because it is a platform from the YORK product line documented in 2020.

For future maintenance, the technician must know exactly which refrigerant is used and follow the procedures specified for this appliance. The refrigerant type must never be determined based on a heat pump’s exterior appearance: we always check the nameplate and model documentation.

ENERGY STAR, cold climate, and rebates

The AirGreen listing for this heat pump states:

ENERGY STAR: No
ENERGY STAR Cold Climate: No

The page does not list any LogisVert provincial rebate amount for this model in its November 26, 2025 update.

For a homeowner whose top priority is obtaining the best financial assistance available, this information may steer the comparison toward other ductless heat pumps. The purchase price of an appliance should not be evaluated separately from its potential rebate, low-temperature performance, and the building’s actual needs.

An essential clarification about SEER, SEER2, and the “18 SEER” designation

The November 2020 YORK documentation classifies this family under “P Series - Up to 18 SEER”. It uses the SEER, EER, and HSPF ratings according to the certification methods for this generation of equipment.

For the 18,000 BTU DHP18CSB21S model, the published data are 16 SEER, 9 EER, and 9 HSPF.

Therefore, these figures should not be arbitrarily converted to SEER2, EER2, or HSPF2. The testing methods are not identical, and a comparison with a recent heat pump should use data certified under the same standard.

For homeowners comparing several systems on our website, this is an important technical detail: a figure displayed in a column is not enough to compare two generations of heat pumps.

Warranty: why system registration matters

The AirGreen specification sheet indicates a warranty of 10 years on the compressor, 10 years on parts, and 0 years on labour, with the possibility of additional warranty coverage depending on the applicable conditions.

The original YORK brochure provides a useful clarification: the advertised standard warranty was 7 years on the compressor and 5 years on parts, while registering the system allowed eligible residential applications to receive 10 years on the compressor and 10 years on parts. Ten years of labour coverage was presented separately as an option requiring the purchase of additional protection.

That is why we recommend keeping the invoice, model and serial numbers, and any registration confirmation. Several years after installation, these documents can make a significant difference when submitting a warranty claim.

What type of project might 18,000 BTU be suitable for?

An 18,000 BTU unit is not automatically intended for a fixed area. Two rooms with the same square footage can have very different heating and cooling loads.

In our assessments in Montréal, Laval, Longueuil, the North Shore, the South Shore, and Montérégie, we consider factors such as the room’s layout, the number and size of the windows, sun exposure, insulation level, ceiling height, the floor where the room is located, and airflow to adjacent areas.

A large open ground floor can sometimes allow a wall-mounted unit to distribute air effectively across several connected areas. Conversely, installing an 18,000 BTU heat pump in a hallway and expecting it to cool several bedrooms whose doors remain closed often results in uneven distribution.

Positioning is therefore just as important as the number of BTUs.

Mistakes we aim to avoid during an installation

A proper wall-mounted heat pump installation involves more than simply mounting an indoor unit and an outdoor unit. Several details affect the long-term result.

We pay particular attention to the condensate drain route, slope, refrigerant connections, defrost water drainage, vibrations, outdoor support, line routing, and indoor unit positioning.

Another often underestimated factor is accessibility. An indoor unit installed too close to the ceiling or wedged against a side wall can make filter cleaning and HVAC maintenance more difficult. A visually discreet installation should not sacrifice the access required for servicing.

Why have this YORK installed and maintained by AirGreen

At AirGreen, our work does not stop at choosing a brand or a capacity displayed on a box. We analyze the entire installation to ensure that the heat pump is truly suited to the building.

For the YORK P Series 18,000 BTU, this means checking the sizing, the 1/4 in. - 1/2 in. piping, the 208/230 V power supply, condenser placement, condensate drainage, air distribution, and warranty conditions.

We serve Montreal, Laval, Longueuil, the North Shore, the South Shore, and the greater metropolitan area for the installation, replacement, maintenance, and servicing of residential and commercial HVAC systems.

Get a quote for your YORK heat pump

To find out whether this YORK P Series 18,000 BTU wall-mounted heat pump is suitable for your house, condo, apartment, or business, contact AirGreen directly.

We can assess the required capacity, installation possibilities, piping route, electrical supply, and other available heat pump options in order to propose a configuration suited to your project.

AirGreen Heat Pumps, Air Conditioning & Heating
514-316-2973
sales@airgreen.ca