Central Heat Pump ADD-ON ARCOAIRE R4H5S Economy | 2 Tons - 24,000 BTU (Coil EVD4X 14.5 in.) - R410A

Cool the whole bungalow and let the heat pump heat as long as the weather allows

In a house heated by an electric furnace, the project often starts with the wish to finally have central air conditioning. The ADD-ON system meets that request and goes further: a coil is installed on the existing furnace and the outdoor unit cools in summer, then heats the house through the same ducts for a good part of the year. The furnace's elements are only used as backup.

The Central Heat Pump ADD-ON ARCOAIRE R4H5S Economy | 2 Tons - 24,000 BTU (Coil EVD4X 14.5 in.) - R410A pairs the R4H5S24AKAAA outdoor unit with the EVD4X24M14A coil. The R4H5S series is the entry level of this Arcoaire family; at 2 tons, it is aimed at the typical bungalow with a basement.

A heat pump rather than a plain air conditioner

On the job site, a central air conditioner and an ADD-ON heat pump look very much alike: an outdoor unit, a copper line, a coil on the furnace and a thermostat. The difference lies in a reversing valve. The air conditioner can only reject the heat of the house outdoors; the heat pump can also do the opposite and capture heat from the outdoor air to heat the house.

In practice, the heat pump takes over fall, spring and a good part of winter. The electric furnace's elements stay ready for the deep cold. You gain air conditioning and give those elements far fewer operating hours.

Which bungalows this size suits

The 2-ton size is meant for mid-sized homes that already have a forced-air electric furnace: a bungalow with a basement, a semi-detached house, a roomy townhouse. With an ADD-ON system, the heat pump is sized first according to cooling needs, since the furnace's elements cover the deep cold. Bigger is not better: an oversized unit reaches the setpoint too fast and leaves humidity in the air.

Two bungalows of the same size can have very different needs. A well-insulated attic, recent windows and an orientation sheltered from the afternoon sun reduce the cooling load; a large west-facing picture window increases it. We do the load calculation, room by room, before confirming the size.

Summer comfort, room by room

The heat pump cools every room served by the ducts. Cool air comes out of the existing grilles and returns to the furnace through the return air openings. In a bungalow, bedrooms facing south or west are often the warmest at the end of the day; we check that each one has enough supply and a return path, even with the door closed.

The basement also benefits from the system, but it needs little cooling. The dampers on the grilles let you reduce the air there and send more toward the main floor. We do this initial balancing at commissioning.

Humidity, the other half of comfort

In cooling mode, the cold coil condenses the humidity in the air, and the water flows through a drain to a floor drain or a pump. A house at the right humidity feels cooler at the same temperature. That is one of the reasons a right-sized unit is better than an oversized one: it runs long enough on each cycle to remove humidity, instead of cooling the air without drying it.

If a humidifier is mounted on the furnace plenum, its location has to be reviewed since the coil is installed in that spot. We identify it during the visit and plan its relocation.

Winter with an electric furnace

A compatible thermostat decides when the heat pump heats alone and when the furnace's elements join in as backup. As long as the heat pump holds the set point, it heats alone; when it is no longer enough, the thermostat brings in the electric elements, then takes them out as soon as it is enough again. The moment the backup comes in is set according to your house and your comfort preferences; we set it with you at commissioning.

This pairing does not carry the cold-climate designation. That is not a flaw in an ADD-ON system: when the cold becomes too sharp for the heat pump, the furnace's elements supplement the heat. You will simply notice that the air from the grilles is milder when the heat pump is heating than when the elements are running, and that cycles are longer. During defrost, the elements may heat for a few minutes to avoid a draft of cool air.

System ratings

The pairing of the R4H5S24AKAAA outdoor unit and the EVD4X24M14A 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. This page therefore gives no rating figure.

When these ratings are confirmed, keep this in mind: SEER2 describes cooling efficiency over an entire season, EER2 its efficiency on a hot day at full demand, and HSPF2 the heat pump's heating efficiency over a season. They apply to the combination formed by the outdoor unit and the coil, and that precise combination is what we write into the quote.

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.

Installation on an electric furnace

Before the quote

We check the condition of the electric furnace and its elements, the airflow of its blower and the duct sizes before the quote. The blower must be able to move the air a 2-ton coil needs, and the return air must keep up. We measure the furnace's air outlet and the free space above it: the 14.5 in. coil must line up with it, or we plan a sealed transition. The ADD-ON system replaces neither the furnace's elements nor its blower; it connects to its air outlet and its controls.

We also look at the electrical panel. In a house heated by an electric furnace, it is often already heavily loaded and does not always have free space for the outdoor unit's breaker, and it is better to know this at the visit than on the day of the work.

The work

The coil is set on the furnace and connected to the plenum, with its condensate drain. Outside, the unit goes on a bracket or a pad, above the snow line, away from roof drips and dryer vents, where defrost water will not freeze on a walkway. The insulated copper line connects the two; we braze it, pressure test it and pull a vacuum before opening the valves.

On the electrical side, the outdoor unit gets a dedicated circuit and a disconnect, and the new thermostat is wired to the furnace and the outdoor unit. Commissioning comes last: refrigerant charge, airflow, defrost, setting of the electric backup and an explanation of the thermostat.

Maintenance and warranty

The furnace filter now works summer and winter: 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, in addition to a check of the electric furnace and its elements. 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.

Request your free estimate for the Central Heat Pump ADD-ON ARCOAIRE R4H5S Economy | 2 Tons - 24,000 BTU (Coil EVD4X 14.5 in.) - R410A. We assess your bungalow room by room and confirm the right size and your grant eligibility before signing.

Available while supplies last.