DURASTAR Sirius Heat Wall-Mounted Heat Pump | 24000 BTU - R454B

24,000 BTU/h still available at -15 °C: primary heating becomes realistic

For a long time, a wall-mounted heat pump was mainly used to cool the home in summer and slightly reduce the heating bill in the fall. As soon as the temperature dropped below -10 °C, baseboard heaters took over again. The DURASTAR Sirius Heat Wall-Mounted Heat Pump | 24,000 BTU - R454B changes that equation for large living areas: its AHRI certificate rates it at 24,000 BTU/h at -15 °C, meaning its full nominal capacity at a temperature that occurs several times each winter in Greater Montreal.

Its certified ratings are 22.3 SEER2, 12.5 EER2 and 13.3 HSPF2. The system is ENERGY STAR certified with the cold climate designation, operates in heating mode down to -30 °C and appears on Hydro-Québec's LogisVert list with a $2,760 rebate.

What the certificate's figures show

• At 8 °C: 26,000 BTU/h, with a range of 11,800 to 28,100 BTU/h and a COP of 3.04
• At -8 °C: 23,000 BTU/h, COP of 2.60
• At -15 °C: 24,000 BTU/h, COP of 2.00
• At -30 °C: up to 10,900 BTU/h, COP of 1.39
• Cooling: 23,000 BTU/h certified, with a range of 16,800 to 24,500 BTU/h

These values come from AHRI certificate 215359265, published by NEEP. DuraStar's commercial sheet lists 21,600 BTU/h at -8 °C; we use the certified value of 23,000 BTU/h because that is the figure used by ENERGY STAR and Hydro-Québec. A COP of 2.00 at -15 °C means the unit delivers two units of heat for every unit of electricity consumed, whereas a baseboard heater delivers only one.

A primary heat source, with a plan for the coldest nights

With these figures, the heat pump can handle most of the heating for the area it serves during most of the season, not just in the fall. We still present it with a clear plan for extreme conditions. Below -15 °C, capacity gradually decreases, reaching 10,900 BTU/h at -30 °C. Existing baseboard heaters, or an electric furnace already installed, therefore remain connected and set a few degrees below the heat pump's setpoint. They start only when the unit is no longer sufficient, which occurs mainly during cold snaps.

A wall-mounted unit heats from a single point. It is highly effective in a large open area, but much less so in closed bedrooms at the end of a hallway. For sizing, we start at approximately 18,000 BTU/h per 1,000 square feet, then adjust according to ceiling height, windows, orientation and insulation quality. A 24,000 BTU unit is therefore suited to open ground floors, large finished basements and through-units where air can circulate easily from one end to the other.

Cooling a large space

In summer, the system delivers 23,000 certified BTU/h, with a seasonal efficiency rating of 22.3 SEER2. Modulation ranges from 16,800 to 24,500 BTU/h. For rooms with extensive south- or west-facing windows, this reserve makes it possible to quickly offset heat accumulated late in the day. The ECO/GEAR function then limits consumption in cooling mode, while Turbo mode is useful when returning home after a hot day.

LogisVert: $2,760 for this system

The system is registered with the LogisVert program under ENERGY STAR ID 3621160, with a $2,760 rebate for owners of existing homes. An enhanced rebate applies to certain multi-unit residential buildings. The amount depends on the list in effect on the installation date; we confirm it before signing and provide the detailed invoice, model numbers and required proof of payment. Our page on the Hydro-Québec efficient heat pump rebate summarizes the conditions.

Electrical service, structure and clearances: the three checks for a 24,000 BTU unit

At this size, installation is no longer simply a matter of drilling a hole and mounting two units. Three factors determine whether the project is feasible and how much it will cost. We check all of them during the in-home assessment.

1. The electrical circuit

The system requires a 208-230 V supply, an MCA of 25 A and a 25 A circuit breaker on a dedicated circuit. A 200 A electrical panel often has enough capacity. In an older home where a 100 A service already supplies baseboard heaters, a water heater and a range, we perform a load calculation before proposing anything.

2. The structure supporting the outdoor unit

The condenser measures 37.24 x 16.14 x 31.89 inches and weighs 130.3 pounds. At this weight, we favour a ground stand on a stable base or a wall bracket anchored to the building structure, such as brick or concrete, rather than only to the siding. The unit must remain above the snow line and protected from roof runoff. Its sound level of 61 dB(A) also requires keeping it away from bedroom windows, including neighbours' windows, which matters greatly in dense Montreal neighbourhoods. The base-pan heater and fin corrosion-resistant coating are included.

3. Clearances and line routing

The refrigerant lines are 3/8 and 5/8 inch. They are precharged for 25 feet and can reach 164 feet, with a maximum elevation difference of 82 feet. Beyond the precharged length, 0.32 ounces of refrigerant is added per foot. This length makes it possible to place the condenser in the least conspicuous location on the property, even far from the indoor unit. The 5/8-inch diameter matters if you want to reuse existing lines: they must match the system, and cleaning and testing them are then included. Our installations remain fully exposed, with no opening of interior walls, and a finished line-set cover can be added as an option. The indoor unit also requires sufficient clearance from the ceiling and on the sides for airflow and servicing.

The indoor unit

The wall-mounted unit measures 42.60 x 9.21 x 13.27 inches and weighs 30.8 pounds. Its sound level ranges from 21 dB(A) in Silence mode to 55 dB(A) in Turbo mode, and its fan offers four levels of 383, 459, 589 and 759 CFM. The vertical louver oscillates automatically, while the horizontal direction is adjusted manually during commissioning. The remote control provides access to the Follow Me, ECO/GEAR, Sleep, Silence, Turbo, Active Clean and Gentle functions. Freeze protection maintains the room at 8 °C during an extended absence. Like any R-454B system, which uses an A2L refrigerant with low global warming potential, the unit includes a factory-installed leak detector. Wi-Fi is not built in; DuraStar offers a separately sold Wi-Fi adapter, and the unit is compatible with the DRSTAT101 wall thermostat.

What is normal in winter

• A five- to ten-minute defrost cycle, during which the indoor unit stops blowing warm air and white vapour escapes outdoors.
• A three-minute delay before the compressor restarts after a shutdown.
• A slight hissing sound when starting or defrosting, and plastic creaking as temperatures change.

A tripped circuit breaker, a persistent error code, an unusual odour or water leaking indoors requires shutting down the unit. Our wall-mounted heat pump repair service can then take over.

Maintenance

1. Clean the indoor filters every two weeks during the season.
2. Clear snow from around the condenser and keep its drainage clear all winter.
3. Schedule annual HVAC maintenance: coils, condensate drainage, electrical connections and a heating operation check.

AirGreen, for a project of this size

A family-owned Montreal company operating for more than fifteen years, AirGreen installs wall-mounted heat pumps in Laval, Longueuil, on the North Shore and the South Shore. We hold the RBQ licences in ventilation, refrigeration and electrical work required by LogisVert, and we carry $5,000,000 in liability insurance. The assessment is free, the quote is written and nothing is signed on-site. We register the unit with the manufacturer and, if the budget requires it, financing options are available.

Book your free estimate for the DURASTAR Sirius Heat Wall-Mounted Heat Pump | 24,000 BTU - R454B: we will verify your electrical panel, the condenser location and your $2,760 LogisVert rebate before providing you with a detailed quote.