Central Heat Pump ADD-ON ARCOAIRE N4H5S Performance | 2 Tons - 24,000 BTU (Coil EVD4X 14.5 in.) - R410A

Make the electric furnace's elements run far less often

A house heated by an electric furnace runs its heating elements every time heat is called for, from fall to spring. The ADD-ON system changes that routine without removing the furnace: 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 its elements are only used as backup, for the cold the heat pump does not cover alone.

The Central Heat Pump ADD-ON ARCOAIRE N4H5S Performance | 2 Tons - 24,000 BTU (Coil EVD4X 14.5 in.) - R410A pairs the N4H5S24AKAAA outdoor unit with the EVD4X24M14A coil. This page focuses on what changes day to day when the heat pump takes over from the elements for most of the heating season.

A heat pump for most of the year

From September to late fall, then from spring until the first warm days, an electric furnace often starts for short periods just to chase away the morning chill. That is exactly the heat pump's territory: it takes over those hours by moving heat from the outdoor air, then keeps heating through a good part of winter. The furnace's elements only come on when the cold becomes too sharp for the heat pump, and spend most of the season at rest.

In summer, the same outdoor unit cools the whole house. For a home that had no central air conditioning, that is often the other half of the decision.

Which homes the 2-ton size suits

The 2-ton size is aimed at mid-sized homes already equipped with a forced-air electric furnace: a bungalow with a basement, a semi-detached house, a roomier townhouse or a modest cottage. With an ADD-ON system, the heat pump is sized first according to cooling needs, since the furnace's elements cover the deep cold. An oversized unit would cool in fits and starts and leave humidity in the air.

Homes heated by an electric furnace and ducts are often older, and their envelope has sometimes been renovated piece by piece. Replaced windows, a re-insulated attic, a basement still unfinished: every detail counts. The room-by-room load calculation confirms whether 2 tons is the right size or whether to go one notch down or up.

How the heat pump heats

A heat pump does not make its heat the way the furnace's elements do: it moves it. In winter, its refrigerant, R-410A, captures the heat contained in the outdoor air; the compressor concentrates it and sends it to the coil sitting on the furnace. The furnace blower passes the house air through that coil, then into the ducts. In summer, a reversing valve flips the cycle and the heat of the house is rejected outdoors.

Sharing with the furnace's elements

A compatible thermostat decides when the heat pump heats alone and when the furnace's electric elements join in as backup. As long as the heat pump holds the set point, the elements stay off; when it is no longer enough, the thermostat brings them in, then takes them out as soon as it is enough again. During defrost, the elements can heat for a few minutes so that the air from the grilles stays warm.

The moment the backup comes in depends mainly on the cold at which the heat pump is no longer enough for your house, and on your comfort preferences. We set it with you at commissioning. This pairing does not carry the cold-climate designation: the furnace's electric backup remains there for the coldest nights.

What does not change

The electric furnace, its elements, its blower and its ducts remain in place, since the furnace continues to serve. The ADD-ON system replaces neither its elements nor its blower: it connects to its air outlet and ties into its controls through the thermostat. Your furnace keeps its role as backup heat, and the heat pump takes on the rest.

Cooling and dehumidification

In cooling mode, the cold coil removes heat and humidity from the house air. The condensed water flows through a drain to a floor drain or a pump. A well-chosen size runs long enough on each cycle to dry the air, which makes the house more comfortable at the same temperature and helps a basement served by the ducts stay drier.

A house designed for an electric furnace alone sometimes has few return air openings. Cooling is more demanding on this point: without a return, a closed bedroom stays warmer than the rest of the house. We check the returns during the visit and, where needed, propose an additional return in the quote.

System ratings

The pairing of the N4H5S24AKAAA 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. We therefore publish no rating figure for this pairing.

Once the ratings are confirmed, HSPF2 will be the most telling one for you: it measures the heat pump's seasonal heating efficiency. SEER2 measures cooling efficiency over a summer, and EER2 the efficiency on a heat-wave day. In an ADD-ON system, these ratings describe the heat pump; the furnace's elements, for their part, still give back as heat the electricity they use, and no more.

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.

What we do on site

The visit

We check the condition of the electric furnace and its elements, the airflow of its blower and the duct sizes before the quote. An older electric furnace may have a blower that is barely enough for the airflow a 2-ton coil requires; we confirm this before proposing this size. We also 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: in a home heated by an electric furnace, it is often already heavily loaded, and the outdoor unit must find its circuit there.

The work

• Coil: set on the furnace's air outlet, connected to the plenum, with its condensate drain to a floor drain or a pump.
• Outdoor unit: on a bracket or a pad, above the snow line, away from roof drips and bedroom windows.
• Refrigerant line: insulated copper, brazing, pressure test and vacuum.
• Electrical: dedicated circuit, outdoor disconnect and thermostat wiring.
• Commissioning: refrigerant charge, airflow, defrost and setting of the electric backup.

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 N4H5S Performance | 2 Tons - 24,000 BTU (Coil EVD4X 14.5 in.) - R410A. We examine your furnace, your ducts and your electrical panel, then confirm the right size and your grant eligibility before signing.

Available while supplies last.