Central Heat Pump ADD-ON ARCOAIRE H4H7T ION 2 stages | 2 Tons - 24,000 BTU (Coil EVD4X 14.5 in.) - R410A

A two-stage heat pump whose ratings are confirmed with your furnace

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 is only used as backup, through its electric elements. The Central Heat Pump ADD-ON ARCOAIRE H4H7T ION 2 stages | 2 Tons - 24,000 BTU (Coil EVD4X 14.5 in.) - R410A pairs the H4H7T24AKAAA outdoor unit, from the ION series, with the EVD4X24M14A coil, with a two-stage compressor.

This pairing has a particularity: its ratings are not read on their own, they are read with the furnace it will be installed on. That is why your furnace's model is the first thing we note during the visit.

Ratings that depend on the furnace

The AHRI certification directory lists the pairing of the H4H7T24AKAAA outdoor unit and the EVD4X24M14A coil only with specific furnaces: the SEER2 and HSPF2 ratings depend on the blower of the furnace in place. We confirm them with your furnace model before the quote. This page therefore publishes no rating figure: it could not apply to every furnace.

This comes from the very way an ADD-ON system works. In this type of installation, the heat pump has no indoor blower of its own: the furnace blower is what moves the air through the coil. The airflow and the power use of that blower are part of the system's efficiency, just like the outdoor unit.

Your furnace's model

The furnace's model number appears on its nameplate, usually inside the access panel or on the side of the cabinet. If you send us a legible photo before the visit, we can start the check sooner; otherwise, we note it on site. We then check whether your furnace is among the combinations listed with this pairing. If it is not, we tell you before the quote and present the options, rather than putting forward ratings that would not apply to your home.

The two-stage compressor

A single-stage compressor is either running or off. The H4H7T series compressor has two stages: a reduced level and full capacity, chosen according to demand. To benefit from it, the thermostat must be able to control both heat pump stages and calling in the furnace's electric elements, and the furnace blower must provide airflow suited to each level. A furnace-only thermostat cannot do this; we replace it with a compatible model and add the missing wiring where needed.

Which homes this size suits

The 2-ton size is aimed at mid-sized homes equipped with a forced-air electric furnace: a bungalow with a basement, a semi-detached house, a roomy townhouse or a modest cottage. With an ADD-ON system, the heat pump is sized first on cooling, since the furnace's elements cover the deep cold. A unit that is too large would run in short cycles and remove humidity poorly, even with two stages.

At equal size, a well-insulated house and a house that loses a lot of heat do not have the same needs. The room-by-room load calculation confirms the size before the quote.

Sharing between the heat pump and the furnace

A heat pump moves heat instead of producing it: in winter, its refrigerant, R-410A, captures heat from the outdoor air and delivers it to the coil. The thermostat follows a sequence: the reduced level first, full capacity when demand rises, then the furnace's electric elements, as auxiliary heat, when the cold becomes too sharp for the heat pump. This pairing does not carry the cold-climate designation; the furnace's elements cover the coldest nights.

As long as the heat pump is enough, the electric furnace's elements stay off; they come in only to top up the heat when demand exceeds what the heat pump can deliver. During defrost, they can also heat for a few minutes so that the air from the grilles stays warm. The moment auxiliary heat comes in is set with you at commissioning, according to your house.

Cooling and humidity

In summer, a reversing valve flips the cycle and rejects the heat of the house outdoors. The cold coil also removes humidity, and the condensed water flows through a drain to a floor drain or a pump. On days when the reduced level is enough, cycles are longer, which helps keep the air dry; during a heat wave, full capacity takes over. We also check the return air, without which a closed bedroom stays warmer than the rest of the house.

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 the existing furnace

The visit

We note the furnace model and check its condition, the airflow of its blower and the duct sizes before the quote. We measure the air outlet and the clearance above the furnace: the 14.5 in. coil must line up with it, or we plan a sealed transition. Finally, we look at the electrical panel, which will have to carry both the heat pump and the furnace's elements, and the possible location of the outdoor unit.

The ducts deserve the same attention. Air conditioning and a heat pump generally require more airflow than the furnace does in heating, and the return air is often what limits the system. We count the returns, check their size and note the ducts that run through an unheated space: those must be insulated so they do not become covered with condensation in summer.

The work

The coil is set on the furnace's air outlet and connected to the plenum, with its condensate drain to a floor drain or a pump. The outdoor unit goes on a bracket or a pad, above the snow line, away from roof drips and dryer vents, where defrost water does not freeze on a walkway. The insulated copper line is brazed, pressure tested and put under vacuum before the valves are opened. The outdoor unit gets a dedicated circuit and a disconnect, and the control wiring connects the thermostat, the furnace and the outdoor unit.

Commissioning

We check the refrigerant charge and the airflow at each of the two stages, in heating as in cooling, then defrost and the complete sequence up to the furnace's electric elements coming in. The furnace blower settings are adjusted to match the confirmed combination. We finish by explaining the thermostat: whether the heat pump is heating alone or with electric auxiliary heat, at which level, and how to change the setpoint.

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. 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 H4H7T ION 2 stages | 2 Tons - 24,000 BTU (Coil EVD4X 14.5 in.) - R410A. We note your electric furnace model and confirm the system ratings, the right size and your grant eligibility before signing.

Available while supplies last.