YORK X Series Mini Split 23 SEER | 9000 BTU 115V

A compact, efficient 115 V wall-mounted heat pump, particularly appealing when the electrical supply imposes constraints

The YORK X Series 23 SEER Mini Split | 9000 BTU 115V occupies a somewhat unique position among wall-mounted heat pumps. Its rated capacity of 9,000 BTU/h, 115 V power supply, and published seasonal efficiency of 23 SEER make it a suitable solution for small residential areas where installing a much larger unit powered by 208/230 V would be unnecessary—or sometimes complicated.

The system consists of the DHX09NWB11S indoor unit and the DHX09CSB11S outdoor unit. YORK identifies it in its documentation as a wall-mounted inverter heat pump from the X Series, designed to heat and cool a single zone. The manufacturer’s brochure also presents the X Series as a range offering up to 23 SEER, with inverter technology, quiet operation, a rugged steel outdoor chassis, corrosion-resistant coating, and demand-based defrosting.

At AirGreen Climatisation & Chauffage, we are particularly interested in this type of model for projects where the question is not simply “how many BTUs are needed?” but also: what electrical circuit is available, what is the actual size of the room, where can the outdoor unit be installed, and how much piping will need to be planned?

In Montreal, Laval, Longueuil, on the North Shore and the South Shore, these details often make the difference between a straightforward installation and one that requires electrical work, finish modifications, or a much more complex line-set route.

Key technical figures for the YORK DHX09NWB11S / DHX09CSB11S

The YORK brochure provides very precise data for this 115 V combination. The rated cooling capacity is 9,000 BTU/h, but the inverter compressor allows modulation from 2,764 to 10,918 BTU/h. In heating mode, the rated capacity reaches 9,900 BTU/h, with a published modulation range of 2,081 to 13,989 BTU/h. The stated efficiency is 23 SEER, 10.5 HSPF, and 13 EER.

For a small wall-mounted heat pump, this modulation range is significant. The unit does not need to run continuously at 9,000 BTU. When the heating or cooling load decreases, the inverter can reduce output to maintain a more stable temperature.

The main technical specifications are as follows:

• Indoor unit: DHX09NWB11S
• Outdoor unit: DHX09CSB11S
• Rated cooling capacity: 9,000 BTU/h
• Cooling range: 2,764 to 10,918 BTU/h
• Rated heating capacity: 9,900 BTU/h
• Heating range: 2,081 to 13,989 BTU/h
• SEER: 23
• EER: 13
• HSPF: 10.5
• Refrigerant: R-410A
• Power supply: 115 V, single-phase, 60 Hz
• MCA: 12 A
• MOCP/MOP: 20 A
• Rated current in cooling: 6.2 A
• Rated current in heating: 6.2 A
• Piping: 1/4 in liquid and 3/8 in gas
• Drain: 5/8 in
• Maximum piping length: 49.2 ft / 15 m
• Maximum elevation difference: 33 ft / 10 m
• Heating operating range: down to -20 °C
• Cooling operating range: up to 46 °C outdoor temperature
• Indoor sound level: 26 to 43 dB(A)
• Outdoor sound level: 53 dB(A)
• Indoor unit dimensions: approximately 33 × 11 × 8 in
• Outdoor unit dimensions: approximately 33 × 21 × 12.5 in
• Wi-Fi: optional with CS532AH adapter
• DRCPX wireless remote control: included

These airflow, sound level, dimensions, connection, and operating range values are those published by YORK for the 9,000 BTU 115 V model in the X Series.

Why 115 V can really simplify certain projects

Most wall-mounted heat pumps of comparable capacity that we encounter today are powered by 208/230 V. The DHX09CSB11S operates at 115 V, which can be an advantage in certain buildings where the existing electrical infrastructure limits the options.

This obviously does not mean that a 115 V appliance can be plugged into just any wall outlet. A professional HVAC installation must always comply with the manufacturer's electrical specifications, the applicable Code, the required protections, and installation requirements.

Here, YORK specifies a minimum circuit ampacity of 12 A and a maximum protection of 20 A.

In an older Montreal duplex, a condo, a small Laval apartment, or a room added on the South Shore, this feature can nevertheless avoid a more complex 240 V configuration when the building conditions permit.

This is exactly the kind of detail we check before recommending a model: a voltage difference that may seem minor on a specification sheet can have a direct impact on feasibility, cost, and the simplicity of the installation.

9,000 BTU: a capacity to size according to the room, not solely according to square footage

A common mistake is to automatically associate a 9,000 BTU capacity with a specific number of square feet.

At AirGreen, we avoid this shortcut.

Two rooms of the same size can have completely different heating and cooling loads. We examine in particular:

• insulation quality;
• the number and size of windows;
• solar orientation;
• the floor of the dwelling;
• ceiling height;
• exposure of exterior walls;
• the number of occupants;
• heat-generating equipment;
• air circulation to adjacent rooms.

A properly sized 9,000 BTU unit can maintain a very stable temperature. The same unit installed in a room with a higher thermal load than its capacity may run continuously without achieving the desired comfort.

The opposite is not better: an oversized heat pump may reach its setpoint quickly but may not run long enough under certain conditions to provide the best possible dehumidification.

Inverter modulation significantly changes how a 9,000 BTU unit operates

The stated minimum cooling capacity of 2,764 BTU/h is particularly noteworthy.

Suppose a bedroom or small living room requires high capacity during a very hot day, followed by much less cooling in the evening. Instead of operating only at full capacity before shutting off, the unit can reduce its output.

The same principle applies to heating, since YORK indicates modulation ranging from 2,081 to 13,989 BTU/h.

This wide range helps limit repeated starts and stops when only a small amount of capacity is needed to maintain the setpoint.

This is one of the factors we consider when comparing an inverter heat pump with an older wall- or window-mounted air conditioner that operates mainly in on/off mode.

Indoor operation as quiet as 26 dB(A)

The indoor unit offers four published airflow levels: approximately 400, 288, 241, and 171 CFM.

The sound pressure level varies accordingly between 43, 38, 32, and 26 dB(A).

For a bedroom, home office, or small living room, this minimum value of 26 dB(A) is significant. It does not mean that the unit always operates at 26 dB(A), since the fan and compressor adjust to the demand. However, it indicates that at low fan speed, indoor operation can be very quiet.

We also pay attention to where the unit is installed. Even a quiet system becomes less comfortable if the air is directed straight at the bed, a workstation, or the sofa.

A good installation is therefore not just about finding enough space on the wall. The actual path of the airflow must also be considered.

A compact unit that makes installation easier in small rooms

The indoor unit measures approximately 33 in. wide, 11 in. deep, and 8 in. high. The outdoor unit is also relatively compact, measuring approximately 33 × 21 × 12.5 in..

In some properties in Longueuil, Montréal, or Laval, we have to work around short walls, high windows, closets, existing pipes, or façade constraints. These dimensions are therefore useful as early as the estimation stage.

We want to leave enough space around the indoor unit to allow proper air intake and make HVAC maintenance accessible. Outdoors, we must also respect the clearances required for air circulation, servicing, and winter operation.

Heating down to -20 °C: information that must be interpreted correctly

YORK indicates a heating operating range of -4 °F to 75 °F, or approximately -20 °C to 24 °C, for the DHX09CSB11S.

This means that the unit is designed to be able to operate down to this minimum outdoor temperature.

However, the minimum operating temperature should not be confused with full capacity guaranteed at -20 °C.

The documentation provided lists the nominal capacities and modulation ranges, but it does not publish a complete capacity curve at every outdoor temperature for the 115 V model in this table.

The AirGreen specifications also indicate values of 8,400 BTU at -8 °C and 8,700 BTU at -15 °C for this combination. For a homeowner planning to use the unit primarily as a heating source during the Quebec winter, we nevertheless recommend analyzing the building’s heating load and comparing the model with newer cold-climate heat pumps when very-low-temperature heating is the absolute priority.

23 SEER, but be careful not to confuse it with 23 SEER2

The YORK brochure dates from 2020 and uses the older SEER, EER, and HSPF metrics.

For this model, the published values are:

23 SEER, 13 EER, and 10.5 HSPF.

It is important not to automatically present this rating as 23 SEER2. The SEER2 testing procedures introduced later are not identical to those used for the older SEER ratings.

For this reason, when comparing it with a modern heat pump advertised at 20 or 22 SEER2, data established using the same methods must be compared before concluding that one unit is more efficient than another.

This technical distinction helps avoid a common error in HVAC product comparisons.

What we look at at AirGreen before installing this YORK X Series system in Montréal, Laval, Longueuil, the North Shore, or the South Shore

1/4 in. – 3/8 in. piping is a critical point when replacing a system

The DHX09CSB11S uses a 1/4 in. liquid connection and a 3/8 in. gas connection. The published maximum length is 49.2 ft, with a maximum elevation difference of 33 ft.

When replacing an old heat pump, we never assume that the existing lines can automatically be reused.

We verify:

The actual line diameter

A refrigerant line whose diameter does not meet the manufacturer's requirements can compromise system operation.

The condition of the copper

A crushed, contaminated, poorly insulated line or one with questionable connections must be corrected.

The total length

When the outdoor unit is located at the other end of the building, the 49.2-foot maximum becomes a real design constraint.

The drain path

The condensate must be properly drained. An inadequate slope can cause water to accumulate or require a condensate pump.

Wi-Fi is available, but it is not included as standard

The DRCPX remote control is included with the X Series. YORK also offers control through the EWPE Smart app, but P and X models require the CS532AH adapter to enable Wi-Fi connectivity.

This distinction should be clearly explained at the time of purchase.

A customer who plans to use only the remote control does not necessarily need this option. However, Wi-Fi can be useful for a cottage, rental property, office, or simply for adjusting the temperature remotely.

Smart defrosting and outdoor construction suited to regular use

For the X Series, YORK highlights a heavy-gauge steel chassis, a corrosion-resistant coating, quiet operation, and demand-based defrosting rather than a rigid cycle.

In winter, defrosting is essential for a heat pump. When the outdoor heat exchanger accumulates frost, the system must periodically remove it to maintain efficient heat exchange.

Defrosting triggered when necessary is intended to limit unnecessary cycles, helping reduce the energy losses associated with this operation.

Warranty: verify registration rather than relying solely on the number of years displayed

The AirGreen listing indicates a 10-year compressor, 10-year parts, 0-year labor warranty for this system, with the possibility of an additional warranty.

The YORK brochure for this generation nevertheless states that the published standard warranty was 7 years on the compressor and 5 years on parts, while residential registration of the system allowed an extension to 10 years on the compressor and 10 years on parts. A separate labor warranty program was also presented.

When installing or purchasing equipment from older inventory, we therefore recommend confirming eligibility, the installation date, registration, and the warranty terms applicable to the specific serial number.

A Scenario Where This Model Makes Perfect Sense

A typical example would be a small independent zone in a property without ductwork: a primary bedroom located far from the central system, a finished office, a small apartment, a home extension, or a space where an old window air conditioner needs to be replaced.

For this type of project, 9,000 BTU can make much more sense than an 18,000 BTU unit chosen “for safety.”

The right approach is to calculate the actual need and take advantage of the system’s modulation capacity.

We prefer to install the right capacity in the right location rather than compensate for poor air distribution with more BTUs.

Who Do We Primarily Recommend the YORK X Series 9000 BTU 115V to?

This system is particularly suitable for:

• a small, well-defined residential zone;
• a bedroom or office where noise level is important;
• a property where a 115 V power supply is an advantage;
• a building without ductwork;
• a renovation where minimizing work is a priority;
• an installation where the refrigerant line run remains within the manufacturer’s limit;
• a homeowner seeking an inverter heat pump offering high seasonal efficiency for its generation.

It is less suitable when several closed bedrooms must be heated from a single unit, when the actual thermal load exceeds 9,000 BTU, or when the project primarily requires cold-climate performance and the certifications of current-generation heat pumps.

Why Entrust Sizing and Installation to AirGreen

A proper wall-mounted heat pump installation in Montreal, Laval, Longueuil, the North Shore, or the South Shore involves more than mounting two units and connecting two pipes.

At AirGreen, we analyze the project as a whole: capacity, electrical supply, indoor location, outdoor clearances, noise, drainage, piping, future maintenance accessibility, and the system’s expected performance in both heating and cooling modes.

For a compact unit such as the YORK X Series 23 SEER 9000 BTU 115V, this preparation allows you to truly benefit from its advantages: low minimum capacity, quiet indoor operation, compact design, and 115 V power supply.

Request Your AirGreen Quote

To determine whether the YORK X Series 23 SEER Mini Split | 9000 BTU 115V, models DHX09NWB11S / DHX09CSB11S, is suitable for your property, contact AirGreen Heat Pumps, Air Conditioning & Heating.

We can assess your space, check the electrical requirements, and compare this YORK with other wall-mounted solutions suited to your project in Montreal, Laval, Longueuil, the North Shore, the South Shore, and Montérégie.

Phone: 514-316-2973
Email: sales@airgreen.ca