Central Heat Pump ADD-ON ARCOAIRE R4H5S Economy | 5 Tons - 60,000 BTU (Coil EVD4X 24.5 in.) - R410A

Add the heat pump now, replace the furnace later

The ADD-ON system adds a heat pump to an existing electric furnace: a coil is installed on the furnace and the outdoor unit heats and cools through the same ducts. The furnace's electric elements are only used as backup. The Central Heat Pump ADD-ON ARCOAIRE R4H5S Economy | 5 Tons - 60,000 BTU (Coil EVD4X 24.5 in.) - R410A pairs the R4H5S60AKAAA outdoor unit with the EVD4X60M24A coil.

Many owners of large homes find themselves in the same situation: the electric furnace still works well, but it is no longer new; the air conditioner has died, or there never was one; and replacing the whole system at once is not the project they want. The ADD-ON lets you move forward in two steps. This page explains how, and what we check today so that the next step goes smoothly.

A project in two steps

Step one: the central heat pump is added to the existing electric furnace. It handles summer cooling and heating in mild and cool weather, and the furnace's electric elements stay as backup for the coldest days. Step two, later: the day the furnace reaches the end of its life, it is replaced without having to redo the outdoor unit or, in many cases, the coil.

This approach spreads the work over time and lets you enjoy air conditioning and heat pump heating right away, without waiting for the furnace to give out.

The furnace's elements work less

Once the heat pump is in place, the furnace's electric elements only come on when the cold exceeds what the heat pump can supply. They therefore accumulate fewer operating hours each winter. The furnace remains essential equipment, though: its elements are what keep the house comfortable during deep cold. Its usual maintenance must continue, and its blower now works all year round, since it also serves the air conditioning. That is why, from the visit onward, we check the condition of its bearings, wheel and motor.

When the furnace has to be replaced

When the day comes, two paths open up. If you keep a furnace, a new electric furnace of the same width, whose blower can serve the system's capacity, generally accepts the existing coil; the outdoor unit stays in place. If you would rather have an air handler fitted with electric backup elements, the outdoor unit can be paired with a compatible model.

In both cases, the new pairing must be verified and its ratings confirmed, as for a new system. We will explain it to you at that time; what matters today is not to close any doors.

The heat pump thermostat installed today can often stay in place with a new electric furnace as well as with an air handler; if needed, it is reconfigured to control the heat pump and the new electric backup.

What we check today for tomorrow

• the width of the furnace cabinet, to match the 24.5 in. coil without compromise;
• the blower's ability to serve a 5-ton system, today as with the future furnace;
• the plenum and the clearance, which will have to accommodate the coil now and later;
• the line set, installed with the diameter and route suited to this size;
• the capacity of the electrical panel, which already feeds the furnace and will also have to feed the backup of the equipment that replaces it one day.

The 5-ton size

The 5-ton size is the largest common residential size. It suits a very large house on two or three levels, a heavily glazed house or an extended house whose duct system serves many rooms, in Longueuil as on the North Shore. These examples are only a guide. In an ADD-ON, we size the heat pump on the cooling load, established by a room-by-room load calculation; if the calculation ends up at a smaller size, we tell you. An oversized unit cools in short cycles and dries the air poorly. If the load falls between two sizes, we present both options and the reason for our choice.

The Economy series and the 24.5 in. coil

The R4H5S60AKAAA unit belongs to Arcoaire's Economy series. The EVD4X60M24A coil is the same as for the other series of this size: the outdoor unit is what sets them apart. The coil is a 24.5 in. format; it must match the width of the furnace cabinet, with a sealed sheet-metal transition when needed, and it fits between the air outlet and the plenum.

System ratings

The pairing of the R4H5S60AKAAA outdoor unit and the EVD4X60M24A 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.

You receive them in writing with the quote; this page shows none.

Day to day, winter and summer

In cool weather, the heat pump heats alone. When the cold deepens and it is no longer enough, the thermostat brings in the furnace's electric elements as auxiliary heat. The auxiliary heat threshold is set at commissioning according to the heat loss of the house and your preferences. The heat pump's air is less hot than the air from the electric elements, its cycles are longer, and a plume of vapour comes out of the outdoor unit during defrost; the furnace's elements may then come on briefly.

In summer, the same unit cools the whole house through the existing ducts. The coil removes humidity from the air, and the water drains through the condensate line to the floor drain or a pump.

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 on the existing furnace

The coil sits on the furnace's air outlet, and a compatible thermostat decides when the heat pump heats alone and when the electric furnace takes over. We check the condition of the furnace, the airflow of its blower and the duct sizes before the quote. The outdoor unit goes on a stand, above the snow line, on a dedicated circuit.

The outdoor unit, bulky at this size, is placed out of roof drip and away from bedroom windows, according to your municipality's rules, with an outdoor disconnect within sight. The insulated refrigerant line set is brazed under nitrogen, pressure-tested and evacuated, then the R-410A charge is adjusted at commissioning, along with the airflow and the thermostat's auxiliary heat threshold.

Maintenance

Replace the system filter according to its format, keep the outdoor unit clear of snow and leaves, and plan annual HVAC maintenance of the coil, condensate drain and electrical connections. In winter, white vapour during defrost is normal.

Keep a note of the furnace's age and of what each maintenance visit finds. The day a technician reports advanced wear, you will have time to plan its replacement rather than face it in the middle of winter.

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 ADD-ON ARCOAIRE R4H5S Economy | 5 Tons - 60,000 BTU (Coil EVD4X 24.5 in.) - R410A. We assess the home room by room and confirm the right size and your grant eligibility before signing.

Available while supplies last.

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