SENVILLE R454B Central Heat Pump | 2 Tons - 24000 BTU

A 24,000 BTU central heat pump designed for Quebec heating, not just air conditioning

When a homeowner is looking for a 2-ton central heat pump for a home in Montreal, Laval, Longueuil, the North Shore, or the South Shore, the nominal capacity of 24,000 BTUs is only a starting point. What really matters is how the unit modulates its output, how much heat it can still produce when the outdoor temperature drops, its seasonal efficiency, its sound level, and its compatibility with the existing ductwork.

The SENVILLE SENDC-24HF is a ducted central system combining air conditioning and heat-pump heating. The Senville documentation provided for this model identifies it as a 24,000 BTU central system from the SENDC-24HF series.

For this configuration, the model numbers used are:

• Outdoor unit: SENDC-24HF-OG
• Indoor unit: SENDC-24HF-IG
• AHRI: 215735326
• ENERGY STAR reference: 3649595
• Refrigerant: R-454B
• Rated cooling capacity: 24,000 BTU
• SEER2: 18.3
• EER2: 11.7
• HSPF2: 10.0
• Advertised minimum heating temperature: -30 °C

The Senville technical sheet also confirms a 208/230 V, single-phase, 60 Hz power supply, an SEER2 of 18.3, and an EER2 of 11.7.

Modulating capacity matters more than a simple “24,000 BTU”

An inverter heat pump does not operate constantly at maximum power. That is precisely one of its advantages.

For the SENDC-24HF, the published operating range is:

• 7,200 to 27,000 BTU/h in cooling mode
• 7,100 to 30,000 BTU/h in heating mode

These values are particularly interesting for a central residential installation. Instead of operating solely in on-off mode at full capacity, the system can adapt its output to the building’s actual needs. The brochure explicitly mentions the use of inverter technology, designed to adjust energy consumption and maintain a more stable indoor temperature.

This modulation becomes important during the mild days of spring and fall. A house that needs only 8,000 or 10,000 BTUs of heating at a given time has no reason to continuously receive 24,000 or 30,000 BTUs followed by a complete shutdown.

Modulating operation can help:

• maintain a more constant temperature;
• reduce perceived variations between cycles;
• improve comfort in different rooms;
• limit repeated starts;
• make better use of long periods of operation at reduced capacity.

What performance really delivers when the temperature drops

For the Greater Montreal climate, we always look beyond the nominal capacity.

According to the data provided for this configuration, the SENDC-24HF produces approximately:

At -8 °C:

• heating capacity: 20,800 BTU/h
• COP: 2,42

At -15 °C:

• heating capacity: 21,600 BTU/h

At the indicated maximum operating outdoor temperature, namely -30 °C:

• capacity: 12,000 BTU/h
• COP: 1,43

This information is essential when comparing several central heat pumps in Montreal. Two models both bearing the “24,000 BTU” label can behave very differently at -8 °C, -15 °C, or -25 °C.

At -30 °C, the fact that the unit can still operate does not necessarily mean that it can cover all of a home’s heat losses on its own. With a stated capacity of 12,000 BTU/h at this temperature, sizing the electric backup heating and analyzing heat losses become particularly important.

At AirGreen, this is exactly why we do not select a central heat pump based solely on a home’s floor area.

COP 2.42 at -8 °C: how to interpret this value

A COP of 2.42 means that under the test condition in question, the heat pump produces approximately 2.42 units of thermal energy for every unit of electrical energy used by the compressor.

This figure helps explain why a heat pump can be an attractive solution compared with electric resistance heating used on its own.

However, COP is not fixed.

It varies in particular according to:

• outdoor temperature;
• setpoint temperature;
• the building’s actual load;
• compressor speed;
• airflow;
• defrost cycles;
• filter condition;
• coil cleanliness;
• ductwork balancing.

The brochure also provides a nominal COP of 3.33 W/W, which corresponds to a different test condition and therefore should not be confused with the COP of 2.42 provided at -8 °C.

SEER2 18.3, EER2 11.7, and HSPF2 10.0

For homeowners comparing several models, three ratings deserve particular attention.

The SEER2 of 18.3 indicates the heat pump’s seasonal cooling efficiency.

The EER2 of 11.7 measures its efficiency under a defined operating condition and allows for more targeted comparisons between units.

The HSPF2 of 10.0 provided in the product data reflects its seasonal heating performance according to the corresponding calculation region. Senville’s documentation also indicates HSPF2-4: 10 and HSPF2-5: 8.

These indicators are useful, but they never replace proper sizing. A highly efficient heat pump installed on an overly restrictive duct system may deliver a much less satisfactory result than its nominal data suggests.

R-454B: an important element of this new generation

The SENDC-24HF uses R-454B refrigerant, with a specified charge of 74.08 oz, or 2.1 kg.

For the customer, the main point is that the installation must be carried out according to the methods and requirements specific to new equipment using this refrigerant.

When replacing an old central heat pump, we therefore systematically check the existing configuration before assuming that the piping can simply be reused.

For this model, the supplied configuration specifies 3/8 in – 3/4 in piping.

This is a particularly important detail. During a central replacement, we regularly encounter homes where the old equipment uses different dimensions. We must not assume that existing piping is automatically suitable for the new unit simply because the old heat pump was also a “2-ton” model.

824 CFM: airflow must match the ductwork

The SENDC-24HF-IG indoor unit delivers up to 824 CFM.

The documentation specifies three airflow rates:

• 824 CFM at high speed
• 759 CFM at medium speed
• 695 CFM at low speed

It also indicates indoor sound levels of 44 / 42 / 28 dB, depending on the selected speed.

The figure of 824 CFM is consistent with what we typically look for around a 2-ton central installation, but the airflow available at the unit is not the only factor.

The system must also be capable of carrying that air.

Why we inspect the ductwork before replacing a heat pump

Let's consider a scenario we regularly encounter when replacing central systems in Greater Montreal.

A home has an old 2-ton heat pump. The owner simply wants to replace the outdoor unit and indoor unit with a new central heat pump of the same capacity.

On paper, this seems simple.

On site, however, we may find:

• an undersized return-air duct;
• several compressed flexible ducts;
• a highly restrictive filter;
• partially closed registers;
• an old, poorly matched coil;
• insufficient airflow to the second floor;
• excessive static pressure.

Installing a modern heat pump without correcting these issues would amount to asking the new equipment to operate under the same poor conditions as the old one.

At AirGreen, we prefer to identify these limitations before installation.

Indoor unit: dimensions to check before ordering

The indoor unit measures:

21.02 in wide × 17.52 in deep × 45.00 in high.

Its net weight is approximately 46.4 lb.

These dimensions are important when the unit must be installed:

• in a basement with a low ceiling;
• in a tight mechanical space;
• in a closet;
• near a water heater;
• under an existing duct network;
• in a location where service clearance is limited.

We must retain sufficient space for future maintenance. An installation that fits to the nearest centimeter may seem acceptable on the day of the work, but can become problematic when a technician needs to access the coil, drain, or an internal component a few years later.

Compact outdoor unit, but its location remains strategic

The SENDC-24HF-OG measures:

35.04 in × 13.46 in × 26.50 in

and weighs approximately 102.29 lb.

Its stated outdoor sound level is 60 dB, with a maximum outdoor airflow of 3,000 CFM.

Its location must account for several typical constraints of properties in Montreal, Laval, Longueuil, and Montérégie.

We examine, among other things:

• clearance around the unit;
• possible snow accumulation;
• water drainage during defrost cycles;
• proximity to a window;
• pedestrian walkways;
• the distance from neighbors;
• the piping length;
• accessibility for maintenance;
• the stability of the base.

A heat pump capable of operating at low temperatures must also remain sufficiently clear during the winter. Installing the unit too close to the ground in an area where snow accumulates can seriously reduce its operating efficiency.

Installation, sizing, and selection of a SENVILLE SENDC-24HF with AirGreen

24,000 BTU is not automatically the right choice for every house

A rule based solely on square footage can lead to improper sizing.

Two 1,500-square-foot houses can have completely different needs depending on:

• the year of construction;
• the insulation level;
• the number of windows;
• orientation;
• air infiltration;
• the basement area;
• the number of floors;
• the type of ductwork;
• the desired indoor temperature.

A very well-insulated house could be oversized with 24,000 BTU, while another property of similar size with significant heat loss could require more capacity or greater auxiliary heating.

This is especially true when considering capacity at very low temperatures.

Auxiliary heating: why planning for 5 kW or 10 kW can be worthwhile

The SENDC-24HF commercial documentation presents 5 kW or 10 kW auxiliary heating options.

Electric auxiliary heat can serve several functions:

• supplement the heat pump during periods of extreme cold;
• help when the heating demand exceeds the available capacity;
• operate according to the thermostat and system configuration;
• provide support during certain operating sequences.

The choice between no element, 5 kW, and 10 kW must not be made at random. In particular, the electrical panel capacity must be verified and the building’s requirements calculated.

Outdoor unit electrical requirements

For the outdoor unit, the provided data indicate:

• 208/230 V
• 1 phase
• 60 Hz
• MCA: 19 A
• maximum protection: 20 A

The Senville data sheet confirms a minimum circuit ampacity of 19 A and a maximum fuse of 20 A for the outdoor unit.

The circuit rating, disconnect switch, wiring, and requirements related to auxiliary heating must be verified in the actual installation context.

A common mistake: replacing the equipment without analyzing the entire system

The compressor often receives all the attention because it is the most visible and expensive component. However, many comfort problems are instead caused by air distribution.

For example, when a customer tells us:

“The main floor is comfortable, but the bedrooms are always too hot in summer,”

changing only the outdoor unit absolutely does not guarantee that the problem will disappear.

We must check:

1. the total airflow;
2. the static pressure;
3. the return size;
4. the airflow to the different zones;
5. the condition of the ducts;
6. the position of the registers;
7. the thermostat location.

This approach is what allows a central heat pump installation to deliver the expected performance in the actual home, not just on a technical data sheet.

Air conditioning: up to 27,000 BTU of modulating capacity

The nominal capacity is 24,000 BTU, but the published range reaches 27,000 BTU/h in cooling.

This does not mean that the unit should be selected as a 27,000 BTU system. The nominal capacity and certification conditions remain the primary references for sizing.

This modulation reserve can nevertheless be useful during certain periods of high demand.

In Montréal, central air conditioning must also manage humidity. An oversized unit that reaches the setpoint too quickly may run in cycles that are too short and remove less humidity than a properly sized system operating for longer periods.

Indoor sound level: only up to 28 dB at low speed

The indoor unit's sound level is listed as:

• 28 dB at low speed
• 42 dB at medium speed
• 44 dB at high speed

For a central system installed near a living area, this factor may be important.

However, the noise produced by the appliance must be distinguished from aerodynamic noise coming from the ducts.

A return grille that is too small or an air velocity that is too high in a duct can create a whistling sound even with a relatively quiet indoor unit.

That is why we consider the entire system when carrying out an HVAC installation.

Optional Wi-Fi

The AirGreen configuration for this model indicates optional Wi-Fi.

For many customers, this is not a primary selection criterion, but this feature can be useful for:

• adjust the temperature remotely;
• change a schedule;
• monitor operation while away;
• take control of the system again before returning home.

We always verify the exact compatibility of the selected control with the proposed installation rather than assuming that an existing thermostat or module can be kept.

ENERGY STAR and eligibility for financial assistance

This heat pump is listed as ENERGY STAR and cold climate, with ENERGY STAR reference 3649595.

The AirGreen data sheet also indicates a provincial rebate of up to $2,496 for this configuration.

Final eligibility nevertheless depends on the program in effect, the property, the installed configuration, and the applicable criteria at the time of the project. We therefore verify the relevant requirements before presenting an amount as guaranteed.

For a homeowner in Montreal, Laval, Longueuil, the North Shore, or the South Shore, this step can significantly change the net cost of replacing a central heat pump.

Warranty: a point to confirm precisely when preparing the quote

The AirGreen data sheet provided for this configuration indicates a 10-10-0 manufacturer’s warranty, with the possibility of additional coverage.

The attached Senville brochure, for its part, mentions 10 years on the compressor and 5 years on parts.

Since these two pieces of information are not identical, the applicable coverage must be confirmed based on the product actually sold, the registration conditions, and the manufacturer's terms at the time of purchase.

We prefer to clarify this point before installation rather than let a customer assume that a generic statement automatically corresponds to their exact warranty.

Who is this 2-ton central heat pump particularly suitable for?

The 24,000 BTU SENVILLE SENDC-24HF R-454B can be an interesting option for a residence equipped with central ductwork when the load calculation confirms that a capacity of approximately two tons is appropriate.

It stands out in particular for:

• its 18.3 SEER2;
• its inverter operation;
• its 10.0 HSPF2;
• its advertised heating capacity down to -30 °C;
• its R-454B refrigerant;
• its maximum indoor airflow of 824 CFM;
• its modulating capacity of up to 30,000 BTU/h in heating;
• its central format, suited to homes already equipped with ductwork;
• its ENERGY STAR Cold Climate certification.

The Senville brochure also describes this model as an inverter central heat pump for year-round heating and cooling using R-454B.

Why have AirGreen install the SENDC-24HF

At AirGreen, our work does not simply involve connecting an outdoor unit to an indoor unit.

Before a central heat pump installation in Montréal, Laval, Longueuil, the North Shore, or the South Shore, we examine the factors that determine the actual result:

• required capacity;
• ductwork;
• airflow;
• electrical supply;
• refrigerant piping;
• drainage;
• outdoor unit location;
• control compatibility;
• auxiliary heating;
• future accessibility for maintenance.

This analysis is particularly important when replacing an existing system. The 3/8 in. – 3/4 in. pipe sizes, the 824 CFM airflow, the maximum electrical protection of 20 A for the outdoor unit, and any need for an auxiliary heating element must all be incorporated into the project design.

A good heat pump installed on an unsuitable infrastructure will deliver mediocre results. A properly sized and adjusted installation, on the other hand, makes it possible to take much better advantage of the features for which the equipment was designed.

Request an AirGreen quote for your SENVILLE central heat pump

Are you considering replacing an existing central heat pump or installing a 24,000 BTU SENVILLE SENDC-24HF?

Contact AirGreen Climatisation & Chauffage. We can inspect your existing installation, ductwork, heating needs, electrical supply, available financial assistance, and the configuration best suited to your property.

We serve Montréal, Laval, Longueuil, the North Shore, the South Shore, and the greater metropolitan area for the installation, replacement, and servicing of central HVAC systems.