SENVILLE R454B 4-Zone Heat Pump | 27000 BTU

Up to four zones on a single outdoor unit: a highly appealing multi-zone solution when several rooms need to be heated and cooled independently

A 4-zone heat pump is not simply a large wall-mounted heat pump with several heads added to it. Sizing, capacity distribution among the rooms, total refrigerant piping length, and how occupants use each zone become critical.

The system presented here is based on the SENVILLE SENA-28HF-MOA outdoor unit, operating with R-454B, with a commercial capacity of approximately 27,000 to 28,000 BTU depending on the technical source used. Senville documentation confirms that this outdoor unit supports 2 to 4 zones, making it possible to create a true four-zone configuration with compatible indoor units.

At AirGreen Heat Pumps, Air Conditioning & Heating, this type of system is particularly relevant in Montreal, Laval, Longueuil, the South Shore, the North Shore, and Montérégie when a property has several bedrooms or distinct spaces that cannot be properly served by a single wall-mounted head.

The AirGreen product page associates this unit with the following specifications:

• Outdoor unit: SENA-28HF-MOA
• Maximum configuration: 4 zones
• AHRI: 215735314
• Refrigerant: R-454B
• Displayed cooling capacity: 27,000 BTU
• SEER: 23.0
• EER: 12.5
• HSPF: 10.5
• ENERGY STAR®: yes
• Cold Climate: yes
• Heating down to -30 °C
• WiFi: included
• Power supply: 220 V
• MCA: 30 A
• MOP: 35 A
• Outdoor sound level: 61 dB(A)
• Displayed provincial rebate: $3,600
• ENERGY STAR ID: 3630061

The manufacturer documentation provided lists 28,000 nominal BTU, a SEER of 23.8, an EER of 12.5, and an HSPF4 of 10.5. This slight difference between 27,000 and 28,000 BTU, or between SEER 23.0 and 23.8, should simply be attributed to the exact certified combination used on the AirGreen product page.

The attached brochure shows two zones, but the SENA-28HF-MOA unit can support four

The brochure’s first page commercially presents a dual-zone configuration, with two indoor units of 12,000 BTU each.

This could give the impression that the SENA-28HF-MOA is only a 2-zone system. However, the technical table clarifies the point: Number of Zones: 2–4.

For this article about a SENVILLE 4-zone heat pump, we are therefore referring to this outdoor unit’s ability to power up to four compatible indoor units.

However, the brochure provided does not specify the exact combination of the four heads that will be used on the AirGreen listing. We should therefore not invent four precise indoor capacities. They must be selected according to:

• the heat load of each room;
• the combinations authorized by Senville;
• the admissible total connected capacity;
• the certification applicable to the complete combination.

The main advantage of a 4-zone system: no longer forcing a single head to condition the entire home

We regularly encounter properties where a wall-mounted heat pump is installed in the living room in the hope that it will also cool the bedrooms farther away.

In an open area, this can sometimes work properly.

In a home with multiple doors, a hallway, and separate bedrooms, air circulation becomes much more limited.

A 4-zone configuration, by contrast, allows an indoor unit to be installed in each strategic area. For example:

• one unit for the living room;
• one for the primary bedroom;
• one for two bedrooms or an upstairs area, depending on the layout;
• one for the basement or an office.

Each zone then gets its own temperature control.

For a home in Montreal, Laval, or Longueuil, this approach can be much more comfortable than a single large heat pump installed in a central area.

Four independent zones do not mean four independent compressors

This is one of the most important concepts to understand about a multi-zone heat pump.

Each head can have its own setting, but the four indoor units share the same SENA-28HF-MOA outdoor unit.

The brochure lists a rated cooling capacity of approximately 28,000 BTU/h, with an operating range of approximately 9,838 to 30,438 BTU/h.

In heating mode, the rated capacity is also listed at 28,000 BTU/h, with a range of approximately 8,218 to 31,000 BTU/h.

The compressor therefore does not produce 27,000 or 28,000 BTUs for each of the four heads.

It distributes its available capacity according to the demands of the different zones.

Why sizing each indoor head is crucial

Suppose a homeowner has four rooms of very different sizes.

Installing four identical indoor units solely to simplify ordering would rarely be the best strategy.

A 150 sq. ft. bedroom and a 500 sq. ft. open living area do not have the same load.

At AirGreen, we therefore want to determine:

1. how many BTUs are actually needed in each zone;
2. whether the four units can be combined with the SENA-28HF-MOA;
3. whether the total connected capacity remains compliant;
4. whether the distribution will remain logical when several zones simultaneously require their full capacity.

This step is particularly important for a multi-zone system because a sizing error in one room can affect overall operation.

SEER from 23 to 23.8: an appealing efficiency for a multi-zone system

The AirGreen data sheet lists a SEER of 23.0, while the brochure table gives 23.8 for the SENA-28HF-MOA. The 12.5 EER is consistent across the information provided.

For a system that can supply four zones, this efficiency is particularly relevant.

A properly used multi-zone system also makes it possible to concentrate comfort where it is actually needed.

If occupants mainly use two rooms during the day, it is not essential to maintain exactly the same setpoint in all four zones.

This approach may be worthwhile in:

• a large house;
• a duplex;
• a multi-bedroom condo;
• a partially occupied basement;
• a home office;
• certain small commercial spaces.

Heating down to -30 °C: a true cold-climate heat pump

The SENVILLE is identified as Cold Climate, and the brochure states that it operates in heating mode down to -22 °F, or -30 °C.

The AirGreen data sheet provides much more useful capacities for understanding its winter performance:

• 30,000 BTU/h at -8 °C
• 27,000 BTU/h at -15 °C
• 14,000 BTU/h maximum at -30 °C

The stated COP is approximately 2.36 at -8 °C and 1.26 at -30 °C.

These figures clearly show why we never simply say that a heat pump “works at -30 °C.”

It can continue heating at this temperature, but its maximum capacity then drops to approximately 14,000 BTU/h according to AirGreen data.

At -15 °C, the capacity remains close to the system’s rated capacity.

The figure of 27,000 BTU/h at -15 °C is particularly important in the Quebec context.

At this temperature, the unit may still provide a capacity comparable to its advertised rated output.

For an installation in Montréal, Laval, Longueuil, Boucherville, or the North Shore, this behavior is often more economically relevant than the performance observed during a few extremely cold hours at -30 °C.

We want to know what proportion of the heating season can be effectively covered by the heat pump before backup systems become necessary.

A four-zone configuration requires consideration of simultaneous operation in winter

Consider four zones that all require substantial heating on a January morning.

The outdoor unit has a specified overall capacity. It must therefore distribute that capacity among all the indoor heads calling for heat.

That is why a homeowner should not simply add the rated capacities listed for the four indoor units and consider that total to be the system's guaranteed output.

The actual maximum output depends on the outdoor unit, the temperature, and the installed combination.

ENERGY STAR and a $3,600 provincial rebate

The AirGreen product sheet indicates:

ENERGY STAR®: yes

Cold Climate: yes

ENERGY STAR ID: 3630061

as well as an advertised provincial rebate of $3,600.

The manufacturer's brochure also identifies the series as ENERGY STAR and highlights operation down to -30 °C.

As always, rebate programs must be confirmed at the time of quotation.

On a multi-zone system, this verification is particularly important because eligibility may depend not only on the outdoor unit, but also on the exact combination of indoor units.

A 1,300-to-1,500-square-foot recommendation to use with caution

Senville indicates an approximate range of 1,300 to 1,500 sq. ft. for the configuration presented in its brochure.

However, it should be noted that this commercial page shows a dual-zone 12,000 + 12,000 BTU configuration.

We therefore should not automatically take this floor area and present it as an absolute rule for every four-zone configuration.

Four small, well-insulated zones may have a different load from four rooms in an older building with a lot of fenestration.

At AirGreen, we use floor area as a starting point, never as the final calculation.

Installation details that become critical when a single outdoor unit supplies four zones

A precharge that can cover up to 100 feet of piping

The SENA-28HF-MOA contains approximately 120.61 oz of R-454B, and the documentation indicates a refrigerant precharge designed for up to 100 feet.

Senville also mentions this 100-foot precharge in its product presentation.

On a four-zone system, this detail deserves particular attention because the lengths add up quickly.

If the outdoor unit is located at ground level and several indoor heads are on different floors or façades, the project's total length can become considerable.

We must therefore calculate precisely:

• the length of each circuit;
• the total length;
• the height differences;
• the fittings;
• the additional charge requirements.

The “1/4 – 3/8” data must not be used as a complete piping plan

The AirGreen specifications indicate 1/4 in – 3/8 in piping.

On a 4-zone system, this general information is not enough to determine the diameter of each branch without knowing which indoor units have been selected.

We always validate the connections port by port according to the actual combination.

This is particularly important when heads with different capacities are combined on the same outdoor unit.

Each indoor head produces its own condensate

Four zones potentially mean four separate drains.

In a simple installation, we can often use gravity drainage.

In a more complex home, some heads may require a much longer route or a specialized solution when a natural slope is impossible.

We therefore plan the drainage at the same time as the refrigerant lines.

An installation where the pipes are properly installed but the condensate cannot drain correctly is still a poor installation.

Automatic vertical and horizontal louvers

The AirGreen specifications indicate automatic vertical and horizontal louvers.

On a four-indoor-unit system, this helps direct the airflow independently in each space.

However, even with motorized louvers, the location of each head remains essential.

We try to avoid:

• an unit blowing directly onto the bed;
• a head hidden behind a beam or partition;
• an installation oriented toward a door rather than the room;
• an indoor unit installed too close to the ceiling without adequate clearance.

Be careful with the figure of 2,130 CFM: it refers to the outdoor airflow

The AirGreen specifications mention approximately 2,130 CFM.

The manufacturer’s table specifies that this value of 2,129.41 CFM corresponds to the maximum airflow of the outdoor unit.

This is not the combined airflow of the four indoor units.

This distinction is important to avoid confusion in the product specifications.

The outdoor unit must be able to freely draw in and discharge this volume of air. It therefore must not be installed in an overly enclosed space or behind an excessively restrictive decorative structure.

61 dB(A) outdoors

The stated outdoor sound level is 61 dB(A).

For a multizone unit of this capacity, the location therefore deserves careful consideration.

We specifically consider:

• bedroom windows;
• the deck;
• neighboring properties;
• walls that may reflect noise;
• service access;
• clearances;
• municipal regulations.

The shortest piping route is not always the best choice if the unit ends up directly below a bedroom.

An outdoor unit weighing 168 lb

The dimensions are:

37.24 in × 16.14 in × 31.89 in

for a weight of approximately 168.43 lb.

A solid installation is therefore essential.

Depending on the property, we can use a suitable base or support, taking snow, access, and long-term stability into account.

208/230 V, MCA 30 A, and maximum protection of 35 A

The brochure indicates:

• 208/230 V
• single-phase;
• 60 Hz;
• MCA: 30 A
• maximum fuse: 35 A
• connection wiring: 14/4 AWG.

This information is consistent with the AirGreen specification sheet.

Before installation, however, we must confirm the panel's actual capacity and the project's specific electrical requirements.

WiFi included and independent zone control

The AirGreen specification sheet indicates WiFi included, and the brochure confirms smart control through Alexa or an app for the system presented.

With four zones, this feature becomes particularly useful.

For example, a homeowner can maintain a different temperature in a bedroom than in the living room and reduce operation in an unused office over the weekend.

The true value of a multi-zone system appears precisely when this independence is used instead of setting all the units to the same temperature year-round.

An interesting user review about comfort, but also about connectivity

The brochure contains a review from a verified Canadian buyer stating that the system made their home comfortable during the summer. However, they mention not using certain connected features as intended.

This illustrates a practical point: the WiFi must be configured correctly, and the user must understand the necessary accessories and applications.

During an AirGreen installation, commissioning should therefore not be limited to checking that the compressor starts.

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.

A Scenario Where Four Zones Make Much More Sense Than One Large Indoor Unit

Consider a two-storey house with three bedrooms and an open main living area.

With a single high-capacity unit in the living room, the bedrooms can remain uncomfortable when their doors are closed.

A four-zone system can allow:

• one unit for the main living area;
• one unit for the primary bedroom;
• two additional units for bedrooms or separate spaces.

The outdoor unit remains a single unit, but air distribution becomes much more precise.

This is exactly the type of project where a 4-zone heat pump in Montreal, Laval, or Longueuil can offer a tangible advantage.

When Two Independent Heat Pumps May Nonetheless Be Preferable

A multi-zone system is not automatically better.

Two separate systems may be appropriate if:

• the zones are very far apart;
• the building consists of two separate dwellings;
• redundancy is a priority;
• the refrigerant line runs become excessively complex.

With a multi-zone system, a single outdoor unit serves all the zones. A failure of this unit can therefore affect several rooms at once.

We always compare this reality with the benefits of a cleaner-looking exterior façade and a single condenser.

Why Choose AirGreen for a SENVILLE 4-Zone Installation

A four-zone installation requires much more planning than a single-zone heat pump.

At AirGreen, we check:

1. the heating load of each of the four zones;
2. compatible indoor capacities;
3. the certified combination with the SENA-28HF-MOA;
4. the length of each line set;
5. the total refrigerant charge;
6. drainage for each indoor unit;
7. wall penetrations;
8. the outdoor location;
9. the 208/230 V power supply;
10. future maintenance needs;
11. the certification and applicable subsidy.

We carry out multi-zone heat pump projects in Montreal, Laval, Longueuil, on the South Shore, the North Shore, and in Montérégie, with particular attention to airflow and the actual sizing of each room.

The SENVILLE SENA-28HF-MOA R454B offers very appealing features for this type of project: up to four zones, ENERGY STAR, Cold Climate, heating down to -30 °C, high seasonal efficiency, WiFi, inverter modulation, and a refrigerant charge suitable for lines up to 100 feet.

Contact AirGreen to get a quote for the SENVILLE R454B 27,000 BTU 4-zone heat pump, determine the right capacities for each of your rooms, and confirm the applicable subsidy in Montreal, Laval, Longueuil, on the South Shore or the North Shore.

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