SENVILLE R454B 3-Zone Heat Pump | 36000 BTU

Three truly independent zones in the home: where the SENVILLE 36,000 BTU becomes more appealing than a single large wall-mounted unit

A 36,000 BTU heat pump may initially seem to be simply a larger heat pump. With the SENVILLE SENA-36HF-MOA, maximum capacity is not the most interesting feature: it is the ability to distribute that capacity among three distinct zones of a property while using a single outdoor unit.

For a home in Montreal, Laval, Longueuil, the North Shore, or the South Shore, this design addresses a problem we regularly encounter at AirGreen. A home may have sufficient total heating and cooling capacity while remaining uncomfortable because the air simply does not reach where it is needed.

A typical example is a property with an open-plan living room and kitchen on the main floor, several bedrooms upstairs, and a finished basement. A single wall-mounted unit installed in the living room cannot properly control all three areas. The SENVILLE 36,000 BTU 3-zone heat pump instead makes it possible to assign one indoor unit to each area and adjust their temperatures separately.

The platform used is the SENA-36HF-MOA outdoor unit, operating with R-454B, providing heating down to -30 °C, with a stated efficiency of 23 SEER2, an EER2 of 13, and a Region 4 HSPF2 of 10.7. The technical documentation also confirms a nominal capacity of 36,000 BTU, a cooling range of 9,000 to 43,000 BTU/h, and a heating range of 10,000 to 44,000 BTU/h.

The SENA-36HF-MOA outdoor model is a multi-zone platform, not merely a fixed configuration

One point deserves clarification from the outset.

The first page of the supplied brochure illustrates a 36,000 BTU two-zone configuration with two 18,000 BTU units, under the commercial reference SENA-36HF-D1818. However, the technical table in the same document identifies the SENA-36HF-MOA system as a multi-zone outdoor unit capable of serving multiple indoor units.

Senville also officially markets this platform in a three-zone configuration, with three indoor units, three remote controls, and three installation kits.

This explains why the outdoor unit number remains SENA-36HF-MOA, even when the indoor combinations change.

For a homeowner, the consequence is important: the outdoor model alone should not be compared. The exact combination of the three indoor units, the corresponding AHRI listing, and their respective capacities must also be verified.

The main characteristics of the AirGreen configuration

For this product sheet, the reported data are as follows:

Senville’s documentation confirms several of these characteristics, including 23 SEER2, EER2 13, HSPF2-4 10.7, MCA 37 A, and maximum fuse 40 A.

Three zones do not mean fixed 12,000 BTU in each room

This is one of the most common mistakes when we explain a multi-zone installation.

An outdoor unit rated at 36,000 BTU connected to three heads does not automatically and continuously distribute 12,000 BTU to each one.

The inverter compressor modulates its output according to demand. The three units can have different capacities, and the available power is distributed according to their operation, within the limits specified by the manufacturer.

Senville’s stated heating range extends from 10,000 to 44,000 BTU/h. The cooling range is from 9,000 to 43,000 BTU/h.

This modulation capability becomes particularly useful in the fall and spring.

Imagine a home in Longueuil comprising:

• a large open area requiring substantial heating;
• two bedrooms exposed to the sun;
• a basement that naturally stays cooler.

At a given moment, a single zone may demand a lot of energy while the other two require very little adjustment. The inverter allows the outdoor unit to adapt its operation rather than treating all three zones as if their needs were identical.

The real advantage of three zones is distribution, not just capacity

In our HVAC assessments, we regularly see properties where the owner wants to increase the number of BTUs to solve the problem of an uncomfortable room.

However, the problem is not always a lack of BTUs.

Suppose a large heat pump is installed in the living room of a two-story house. It can quickly reach 22 °C in the living room, while a bedroom upstairs remains at 18 °C.

Installing an even larger head in the living room will not necessarily solve the problem. This unit's thermostat will quickly detect that its own zone has reached the setpoint and reduce its output before enough heat reaches the bedroom.

With three zones, we can work differently:

Zone 1: open-concept main-floor area
Zone 2: upper floor and bedroom area
Zone 3: basement, office, or another separate space

The result is often much more logical from a comfort standpoint.

Each zone can have its own temperature

The multi-zone heat pump allows the indoor units to be adjusted individually.

For example, a family could maintain:

• 21 °C on the main floor;
• 19 °C in the bedrooms at night;
• 18 °C in a rarely used basement.

When the basement becomes a family room in the evening, its setpoint can be increased independently of the other two areas.

This is one of the most concrete advantages of a 3-zone heat pump in Montreal: you do not have to condition every room in exactly the same way.

However, an important limitation must be kept in mind. Units connected to the same outdoor unit generally need to operate in compatible modes. One unit cannot continuously call for heating while another requests cooling from the same conventional compressor.

Down to -30 °C, but with capacity that varies with temperature

The Senville brochure indicates that the unit can continue operating in heating mode down to -22 °F, or approximately -30 °C.

The AirGreen specification sheet provides even more important information: the capacity available at different temperatures.

At -8 °C, approximately 38,000 BTU/h is indicated.

At -15 °C, the published capacity is 36,000 BTU/h.

At -30 °C, the listed maximum capacity drops to approximately 22,400 BTU/h.

This behavior must be understood before deciding whether the heat pump can become the home's sole heating system.

Even though the unit continues to operate at -30 °C, it does not necessarily provide the nominal 36,000 BTU. If the house loses 30,000 BTU/h at that temperature, a supplementary heating source will still be necessary.

22,400 BTU at -30 °C remains a significant capacity

The difference from a unit that stops operating completely in extreme cold is significant.

With approximately 22,400 BTU/h available at -30 °C, the heat pump can continue reducing the workload required of electric baseboard heaters or another backup system.

Its maximum COP published at -30 °C is 1.47.

This means that under this test condition, the heat pump still transfers more heat than electric resistance heating can produce using the same amount of electricity, even though its advantage is much smaller than at milder temperatures.

At -8 °C, its indicated COP of 2.12 is significantly more favorable.

This distinction makes a major difference to the annual bill: most heating hours during a winter in Montreal, Laval, or Longueuil do not occur at -30 °C.

38,000 BTU at -8 °C and an indicated LogisVert incentive of $4,560

The AirGreen product sheet indicates a heating capacity of 38,000 BTU/h at -8 °C.

Hydro-Québec currently provides, when all program conditions are met, assistance of $120 per 1,000 BTU/h at -8 °C for a cold-climate ENERGY STAR-certified heat pump.

The calculation is therefore:

38 × $120 = $4,560

This is the amount of 4 560 $ indicated on the AirGreen product sheet.

However, this financial assistance should never be considered automatic simply because a model carries ENERGY STAR certification. The installed combination, the date of the work, and compliance with all program requirements must be confirmed at the time of application.

23 SEER2 and EER2 13: suitable ratings for an efficient multizone system

The technical table provided by Senville indicates a SEER2 of 23 and an EER2 of 13.

For a 36,000 BTU multizone system, this efficiency level is particularly appealing because three spaces can be controlled without having to install three separate outdoor units.

However, actual consumption will depend on several factors:

• setpoint temperature;
• building insulation;
• solar exposure;
• air infiltration;
• number of active zones;
• sizing of the indoor units;
• frequency of door opening;
• outdoor temperature.

We therefore advise against calculating annual savings based solely on SEER2.

A heating range of up to 44,000 BTU

The nominal heating capacity is 36,000 BTU, but the system can modulate up to approximately 44,000 BTU/h under certain conditions.

This reserve can be useful when high demand temporarily occurs in several zones.

Conversely, capacity can drop to approximately 10,000 BTU/h.

This range allows the compressor to avoid operating continuously at maximum output on a mild day.

AirGreen installation of a SENVILLE 3-zone system: the details that truly change the outcome

The first task is to choose the three right zones

With three indoor units, it would be easy to think that all you need to do is select three rooms.

Instead, we analyze the property's thermal zones.

An open area containing the kitchen and living room can constitute a single zone even if it contains several rooms. Conversely, two bedrooms located on opposite sides of a long corridor may have very different thermal behavior.

We specifically check:

• the location of the stairs;
• the orientation of the windows;
• the ceiling height;
• the insulation;
• the area that is actually open;
• the doors that are usually closed;
• the pipe route;
• the possible drainage location;
• the comfort desired in each area.

A typical configuration we encounter in Greater Montreal

For a family home with a finished basement, a logical distribution might be:

Main zone: 18,000 BTU

Large open area combining the kitchen, dining room, and living room.

Secondary zone: 9,000 BTU

Floor containing bedrooms or an office.

Secondary zone: 9,000 BTU

Basement or family room.

This is only a design example. Another house might require 12,000 + 12,000 + 12,000 BTU or a different combination.

What matters is the heating load of each zone, not achieving a perfectly symmetrical distribution.

The attached brochure should not be used to automatically select the three indoor units

The brochure provided illustrates a version with two 18,000 BTU units, because it is a dual-zone commercial page based on the same SENA-36HF-MOA.

For a 3-zone installation, Senville officially confirms that a three-zone configuration includes three indoor units and three 16 ft line sets when this option is ordered.

At AirGreen, we therefore verify the compatibility of the exact combination before ordering the equipment.

R-454B and precharge capable of covering up to 125 ft

The system uses R-454B.

The accompanying documentation states:

• refrigerant charge: 134.04 oz;
• stated precharge: 125 ft;
• minimum outdoor temperature in heating mode: -30 °C.

On a three-zone installation, this available length becomes particularly relevant because the lines from all three units must reach the same outdoor unit.

A two-story house can easily require:

• 20 ft for the first head;
• 35 ft for the second;
• 45 ft for the third.

We plan the routes before deciding where to place the compressor. An outdoor location chosen solely for its appearance may require several additional dozen feet of unnecessary piping.

1/4–1/2 piping: the diameter must be validated for each zone

The AirGreen data sheet specifies 1/4 in – 1/2 in piping.

However, for a multi-zone system, we always confirm the diameters based on the capacity and model of each indoor unit. A 9,000 BTU head and a higher-capacity unit may not use exactly the same connections.

This is another reason to order the lines after validating the complete combination.

An outdoor unit weighing more than 200 lb

The SENA-36HF-MOA measures approximately:

38.58 × 16.34 × 38.39 in

and weighs 211.86 lb.

This weight affects the choice of bracket.

For a heat pump of this size, we want a stable installation that can withstand vibrations, snow, and defrost cycles.

A small, lightweight bracket used for a 9,000 BTU heat pump is not automatically suitable for an outdoor unit weighing more than 200 lb.

3,038 CFM: this is the outdoor airflow

The technical data sheet indicates approximately 3,037.2 CFM and an outdoor sound level of 65 dB(A).

It is important to clarify that this figure corresponds to the maximum airflow of the outdoor unit, not the combined airflow of the indoor heads.

An outdoor airflow of more than 3,000 CFM requires adequate clearances.

We therefore avoid enclosing the unit in a space that is too narrow, beneath a low structure, or against several walls that could encourage recirculation of the discharged air.

65 dB(A): the outdoor location deserves careful consideration

At the advertised 65 dB(A), the outdoor unit is not something we want to place thoughtlessly directly beneath a bedroom window.

In dense areas of Montreal, Laval, and Longueuil, we also consider proximity to:

• the neighboring property;
• a patio;
• a balcony;
• bedrooms;
• a narrow passage between two buildings.

Walls can reflect noise and make an installation more audible than a figure measured under standardized conditions might suggest.

A -30 °C heat pump must be installed to operate in snow

Buying a heat pump capable of heating down to -30 °C makes little sense if the outdoor unit ends up partially buried after a storm.

We therefore allow sufficient clearance to:

• protect the heat exchanger from snow accumulation;
• allow for defrosting;
• prevent ice from blocking the bottom of the unit;
• facilitate future maintenance.

Defrosting produces water, and that water quickly freezes on an outdoor surface in January. The space beneath and around the compressor must accommodate this accumulation without compromising operation.

MCA 37 A, MOP 40 A, and 208/230 V power supply

The documentation specifies a 208/230 V, single-phase, 60 Hz power supply, with a voltage range of 187 to 253 V.

The MCA is 37 A, and the indicated maximum protection is 40 A.

These values should be used for electrical planning for the outdoor unit.

We never size a circuit based solely on the advertised 36,000 BTUs.

WiFi, Alexa, and three zones: a much more useful feature than with a single head

Senville highlights app-based control as well as Alexa integration for this series. The manufacturer also confirms remote scheduling features on its official three-zone configuration.

With three zones, this feature truly shows its value.

Rather than searching for three different remote controls, the owner can adjust several zones directly from their phone.

For a secondary residence, it is also possible to adjust the settings before arrival.

Self-diagnostics and leak detection

The Senville documentation mentions a monitoring system capable of reporting certain problems, including refrigerant-related anomalies.

These functions facilitate diagnosis, but they do not replace an inspection when a zone stops heating properly.

An apparent problem with just one head may stem from several factors:

• clogged filter;
• dirty indoor fan;
• sensor;
• drainage;
• communication;
• refrigerant;
• incorrect configuration.

A multi-zone system must therefore be diagnosed as a whole.

Maintenance is tripled indoors

A three-zone heat pump has three indoor units.

This also means:

• three sets of filters;
• three heat exchangers;
• three fans;
• three condensate drains;
• three points to check during maintenance.

A head installed in an open kitchen can become dirty much faster than a bedroom head. Therefore, the three units do not always need to have exactly the same level of dirt.

We recommend checking each filter regularly rather than treating the system as a single appliance.

Beware of oversizing small rooms

A common mistake with multi-zone systems is thinking that the more BTUs a head has, the better it will perform.

In a small bedroom, an oversized unit can reach its setpoint very quickly and run for less time at low speed.

The goal is therefore to select the appropriate capacity for each zone, even if the outdoor unit could accept a larger total combination.

Warranty

This system is covered for 10 years on the compressor, 10 years on parts and 6 years on labor, straight from the distributor, with the option of additional coverage.

Which properties do we primarily recommend this 3-zone SENVILLE for?

The SENVILLE 36,000 BTU is particularly suitable for:

• a two-story house with a basement;
• three physically distant areas;
• a large open-concept area combined with enclosed rooms;
• a condo or dwelling with several distinct thermal zones;
• a property where the goal is to limit the number of outdoor units;
• a project seeking a cold-climate ENERGY STAR heat pump;
• a homeowner who wants to continue using their heat pump down to -30°C;
• an installation where each zone must be able to have its own setpoint.

It is less logical when a single large open area needs to be treated. In that case, a properly sized single-zone heat pump may be simpler and more economical.

Why AirGreen sizing matters more for a multizone system

A three-zone system involves far more variables than a single-zone unit.

We need to match:

the outdoor unit capacity,
the three heating loads,
the indoor unit models,
the refrigerant line lengths,
the electrical requirements,
the drains,
the locations,
the AHRI certification,
the applicable rebate.

That is why we pay particular attention to the design before the HVAC installation.

At AirGreen Heat Pumps, Air Conditioning & Heating, our goal is not simply to install three heads on three available walls. We strive to create three zones that truly correspond to how the property is occupied.

SENVILLE 3-zone heat pump installation in Montreal, Laval, Longueuil, the North Shore, and the South Shore

The 36,000 BTU SENVILLE SENA-36HF-MOA R454B combines a wide modulation range, cold-climate certification, operation down to -30°C, a SEER2 of 23, substantial low-temperature heating capacity, and the ability to distribute comfort across three areas.

However, its main advantage does not lie in a single statistic.

It offers the possibility of cooling and heating three different zones with a single outdoor unit, provided that each zone is properly sized.

Contact AirGreen for a quote and an assessment of your 3-zone SENVILLE heat pump project in Montreal, Laval, Longueuil, the North Shore, or the South Shore. We can verify the combination of the three indoor units, the AHRI certification, low-temperature capacity, electrical installation, refrigerant line routing, and the applicable LogisVert rebate before the work begins.

Warranty: 10 years on the compressor, 10 years on parts and 6 years on labor, straight from the distributor.