Central Heat Pump ARCOAIRE R4H5S Economy | 3 Tons - 36,000 BTU (Air Handler FJMA4X) - R410A
Replace the central air conditioner and the electric furnace with a single heat pump
In many large homes in the region, comfort relies on two units installed long ago: an electric furnace in the basement for winter and a central air conditioner outside for summer. When one or the other reaches the end of its life, a central heat pump can replace both, reusing the existing ducts. The Central Heat Pump ARCOAIRE R4H5S Economy | 3 Tons - 36,000 BTU (Air Handler FJMA4X) - R410A pairs the R4H5S36AKAAA outdoor unit with the FJMA4X36L0BB cabinet, which takes the furnace's place.
Its certified ratings are 14.3 SEER2, 12.0 EER2 and 7.5 HSPF2. The R4H5S series is Arcoaire's Economy series: a conventional pairing, sized for a large home.
Which homes
The 3-ton size is aimed at large homes that already have ducts: a large bungalow with a finished basement, a two-storey house, a detached house with many rooms. It handles the cooling of every room served and most of the heating.
Be careful, however, not to copy the old air conditioner's size automatically. Many were chosen one size too big, and the house has often changed since: replaced windows, an insulated attic, a finished basement. Our room-by-room load calculation confirms the right size before any quote.
What stays
- The duct system, if it is in good condition and large enough for the heat pump's airflow.
- The supply and return grilles, with corrections where needed.
- The cabinet location, where the old furnace stood, with its plenum and return air.
- The thermostat location, if it is well placed in the house.
The duct system is the centrepiece. A central heat pump only delivers its full efficiency if the airflow keeps up; we therefore check duct sizes and the air return before confirming they can stay as they are.
What gets replaced
- The electric furnace gives way to the FJMA4X36L0BB cabinet, an air handler that houses the coil, the blower and the backup electric heating elements.
- The outdoor air conditioner gives way to the R4H5S36AKAAA unit, which cools in summer and heats in winter.
- The thermostat is replaced with a model designed for a heat pump with backup.
- The outdoor unit's pad is generally replaced with a raised stand, for the reason explained below.
The old air conditioner's refrigerant line is assessed during the visit: its condition, its route and its compatibility determine whether it can be kept or whether a new line is preferable. We state this in the written quote.
Why the outdoor unit must be raised
An air conditioner only runs in summer; sitting on the ground, it has nothing to fear from snow. A heat pump, on the other hand, works all winter. If snow surrounds it, air flows poorly through its coil and its efficiency drops. During defrost, it also produces meltwater, which must drain under the unit without freezing against it.
That is why we install the outdoor unit on a raised bracket or stand, above the snow line, away from roof drips and corners where snow piles up. We also avoid dryer vents and, as far as possible, bedroom windows. A raised stand also makes maintenance easier and keeps the unit away from the leaves and debris that pile up on the ground in the fall.
The R4H5S and FJMA4X pairing
The two units are certified together and linked by an insulated copper refrigerant line. They run on R-410A: in winter, the refrigerant captures heat from the outdoor air, the compressor concentrates it and the cabinet's coil releases it to the air of the house; in summer, a reversing valve turns the cycle around and the heat is released outdoors. Because it moves heat instead of producing it, the heat pump delivers more energy than it uses.
What the certificate shows
The certificate lists 20,400 BTU/h at -8 °C and 15,800 BTU/h at -15 °C. The two points are measured separately; we report each one as published. At the -15 °C point, the COP is 2.02.
Compared with the nominal size of 36,000 BTU, the listed capacity represents about 57% at -8 °C and 44% at -15 °C. These figures show what you gain over the electric furnace, which has a COP of 1, and what is left to the backup in deep cold.
These figures come from certificate AHRI 210999017, as published in the AHRI certification directory.
Backup heat in deep cold
The cabinet's backup elements play, in a way, the role of the old furnace, but only when needed. In deep cold, they supplement the heat pump's heat, then switch off as soon as it is enough again. The thermostat manages this handover.
In a large home, the backup is a significant electrical load. We size it from the load calculation and the capacity of the electrical panel, often reusing part of the old furnace's power supply; everything appears in the written quote.
The ratings and what they mean
The SEER2 of 14.3 measures cooling efficiency over a full summer; the EER2 of 12.0, cooling efficiency at full demand on a hot day. The HSPF2 of 7.5 measures heating efficiency over a season: it is the most telling rating for a home heated most of the year. COP is read at a specific temperature; at -15 °C, this pairing delivers about twice the energy it uses.
These are the ratings of a conventional system. If you are aiming for higher ratings or a grant, we will also show you pairings of comparable size that meet those goals.
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.
Installation by AirGreen
The job
- Visit: load calculation, inspection of the ducts, return air and electrical panel, choice of the outdoor location.
- Removal of the air conditioner, with recovery of the refrigerant, and of the electric furnace.
- FJMA4X cabinet: installed where the furnace stood, connected to the plenum and return air, condensate drain to a floor drain or a pump.
- Outdoor unit: on a raised stand, above the snow line.
- Refrigerant line: insulated copper, brazing, pressure test and vacuum.
- Electrical: dedicated circuit, outdoor disconnect, power to the backup and a heat pump thermostat.
- Commissioning: refrigerant charge, airflow, defrost, settings, then an explanation of how everything works.
Maintenance and warranty
Check the cabinet filter every month in season and replace it according to its format. Clear the outdoor unit after storms and do not cover it in winter; unlike the old air conditioner, it must stay free all year. Plan annual HVAC maintenance of the coils, the condensate drain and the electrical connections. The white vapour during defrost, in winter, 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.
Request your free estimate for the Central Heat Pump ARCOAIRE R4H5S Economy | 3 Tons - 36,000 BTU (Air Handler FJMA4X) - R410A. We assess the home room by room and confirm the right size and your grant eligibility before signing.