Central Heat Pump ADD-ON ARCOAIRE R4H5S Economy | 2.5 Tons - 30,000 BTU (Coil EVD4X 17.5 in.) - R410A
Add a heat pump to a home heated by an electric furnace, starting with the panel
In a house heated by an electric furnace, the panel already carries all of the heating. The ADD-ON system hands a good share of it to the heat pump: a coil is installed on the existing furnace and an outdoor unit heats and cools through the same ducts. The furnace stays in place and is only used as backup: its electric elements cover the cold the heat pump does not cover alone.
The Central Heat Pump ADD-ON ARCOAIRE R4H5S Economy | 2.5 Tons - 30,000 BTU (Coil EVD4X 17.5 in.) - R410A pairs the R4H5S30AKAAA outdoor unit with the EVD4X30M17A coil. The R4H5S series is the entry level of this Arcoaire family. Before talking about the unit, we look at something often forgotten in an electrically heated house: the electrical panel.
Why start with the electrical panel
In a house heated by an electric furnace, the panel already feeds the furnace's elements, often the largest load in the house, on top of the range, the water heater and the dryer. Sometimes it is enough to add a heat pump; sometimes it is already full, or its capacity is taken up by a spa or a charging station. The outdoor unit of a 2.5-ton system requires a dedicated circuit and a nearby disconnect, and it comes on top of the furnace's elements, which stay connected for backup: that needs planning.
During the visit, we open the panel, note the free space and the existing loads, and check the cable route to the outdoor unit. If the panel requires work, we state it clearly in the quote. That way, you know before signing everything the project includes.
What the ADD-ON system adds
The coil sits on the furnace's air outlet, in the supply plenum. A copper line connects it to the outdoor unit. The furnace blower pushes the house air through the coil, then into the existing ducts: no new grilles, no unit on the wall. The furnace's heating elements and their power supply are not touched: they stay in place for backup.
Which homes this size suits
The 2.5-ton size is aimed at roomier homes: a split-level house, a bungalow with a finished basement, a family-sized cottage or a generous semi-detached house. With an ADD-ON system, the heat pump is sized first on cooling needs, since the furnace's elements cover the deep cold. A unit larger than needed would cool in fits and starts and leave humidity in the air.
A split-level house has its own challenges: the offset levels do not all receive air the same way, and the room above the garage is often the hardest to cool. The room-by-room load calculation accounts for insulation, windows and orientation, and it is what confirms the size.
How the heat pump heats and cools
A heat pump does not produce heat: it moves it. In winter, its refrigerant, R-410A, captures heat from the outdoor air; the compressor concentrates it and sends it to the coil. In summer, a reversing valve flips the cycle, and the heat of the house is rejected outdoors. The air coming out of the grilles when the heat pump is heating is milder than that of the furnace's elements, and the cycles are longer: that is normal heat pump operation.
Backup from the furnace's elements
The thermostat decides when the heat pump heats alone and when the furnace's electric elements come in as auxiliary heat. Every hour the heat pump is enough is an hour those elements stay off. The moment auxiliary heat comes in takes two things into account: the cold at which the heat pump is no longer enough for your house, and the comfort you expect when the outdoor temperature drops quickly.
This pairing does not carry the cold-climate designation; in an ADD-ON system, the furnace's elements are precisely what covers the coldest nights. During defrost, they may also heat for a few minutes so that the air from the grilles stays warm. We set the parameters with you at commissioning.
Cooling and humidity
In cooling mode, the cold coil removes heat and humidity from the air. The condensed water flows through a drain to a floor drain or a pump; if a humidifier already empties into the same drain, we arrange the two drains so that both flow without backing up. A right-sized unit runs long enough on each cycle to dry the air, which makes the house more comfortable at the same temperature.
We also check the return air. A closed bedroom without a return stays warmer than the rest of the house, and a home designed for a furnace alone sometimes has too few returns for cooling.
The 17.5 in. coil on the furnace
We check the condition of the furnace, the airflow of its blower and the duct sizes before the quote. The blower must be able to move the airflow of a 2.5-ton coil. The 17.5 in. coil must line up with the furnace's air outlet; if it does not, we fabricate a sealed transition. We also measure the clearance above the furnace and identify any humidifier mounted on the plenum, whose location will need to be reviewed.
System ratings
The pairing of the R4H5S30AKAAA outdoor unit and the EVD4X30M17A coil is not listed with SEER2 ratings in the AHRI certification directory. We confirm the ratings of the complete system before the quote; they also determine grant eligibility. No rating figure is therefore published here.
LogisVert
This pairing does not carry an amount on Hydro-Québec's LogisVert list of October 19, 2026. If the grant matters for your project, we will point you to an eligible pairing of comparable size. Our page on the grant for efficient heat pumps summarizes the program's conditions.
The job
The steps
- Visit and load calculation: rooms, insulation, windows, furnace, ducts, return air and electrical panel.
- Coil: set on the furnace's air outlet, connected to the plenum, with its condensate drain.
- Outdoor unit: on a bracket or a pad, above the snow line, away from roof drips, dryer vents and bedroom windows.
- Refrigerant line: insulated copper, brazing, pressure test and vacuum before the valves are opened.
- Electrical: dedicated circuit, outdoor disconnect and control wiring, on a panel checked to carry the heat pump in addition to the furnace's elements.
- Thermostat: replaced with a model that manages the heat pump and electric auxiliary heat, since a furnace-only thermostat cannot control a heat pump.
- Commissioning: refrigerant charge, airflow, defrost, the furnace's elements coming in and an explanation of the thermostat.
Maintenance and warranty
The furnace filter now works all year: check it every month and replace it according to its format. Keep the outdoor unit clear of snow and leaves, with no cover in winter since it heats. Plan annual HVAC maintenance of the coil, the condensate drain and the electrical connections; the electric furnace and its elements also deserve a check. In winter, white vapour during defrost is normal.
Warranty: 10 years on the compressor, 10 years on parts and 6 years on labor.
AirGreen, for the life of the installation
A family business active for more than fifteen years in Montreal, Laval, Longueuil, the North Shore and the South Shore, we hold RBQ licences for ventilation, refrigeration and electrical work and carry $5,000,000 in liability insurance. The in-home assessment is free, the quote is in writing, and our financing options let you choose the right unit rather than the cheapest one.
The electrical licence makes full sense in an electrically heated home: checking the panel and connecting the outdoor unit are part of the same job as the refrigeration circuit and the connection to the ducts.
Request your free estimate for the Central Heat Pump ADD-ON ARCOAIRE R4H5S Economy | 2.5 Tons - 30,000 BTU (Coil EVD4X 17.5 in.) - R410A. We assess the home room by room, check your electrical panel and confirm the right size and your grant eligibility before signing.
Available while supplies last.