Central Heat Pump ADD-ON ARCOAIRE N4H5S Performance | 2.5 Tons - 30,000 BTU (Coil EVD4X 17.5 in.) - R410A
Two and a half tons of cooling and heating on a family-sized furnace
In a family home heated by a forced-air electric furnace, the duct network already serves every room, from the basement to the bedrooms. The ADD-ON system builds on that network: 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 is only used as backup, through its electric elements.
The Central Heat Pump ADD-ON ARCOAIRE N4H5S Performance | 2.5 Tons - 30,000 BTU (Coil EVD4X 17.5 in.) - R410A pairs the N4H5S30AKAAA outdoor unit with the EVD4X30M17A coil. At this size, the coil moves up to 17.5 in.: a detail that matters when it is set on the furnace, and one we check from the first visit.
The 17.5 in. coil
The smaller sizes in this family use a narrower coil; this one moves up to 17.5 in. to accommodate the heat exchange surface of a 2.5-ton system. Furnaces serving larger homes often have a wider cabinet, and the coil then lines up with it directly. When the furnace is narrower or wider, we fabricate a sealed transition so that all the air passes through the coil, with no leakage at the sides.
We also measure the height available between the top of the furnace and the joists. A finished basement, with a finished ceiling around the mechanical room, can limit the space for the coil and the rebuilt plenum; better to know this before the quote than on the day of the work.
Which homes this size suits
The 2.5-ton size is aimed at roomier homes: a bungalow with a finished basement, a family-sized cottage, a split-level house or a generous semi-detached house, as found in Laval, on the North Shore or on the South Shore. With an ADD-ON system, the heat pump is sized first on cooling needs, since the furnace's elements cover the deep cold.
Floor area is not enough to choose. A well-insulated house with recent windows may be fine with the next size down; a house with lots of glass or a poorly insulated attic may need more. The room-by-room load calculation confirms the size. An oversized unit would run in short cycles, leave humidity in the air and create differences between rooms.
What the furnace must be able to do
In an ADD-ON system, the furnace blower is what pushes the air through the coil. A 2.5-ton coil requires an airflow that not every furnace can deliver, especially the smaller ones. We check the condition of the furnace, the airflow of its blower and the duct sizes before the quote. We also count the return air openings: a family home built for a furnace alone sometimes has too few for cooling, and that is often what limits the system.
How the system works
A heat pump moves heat instead of producing it. In winter, its refrigerant, R-410A, captures heat from the outdoor air; the compressor concentrates it and sends it to the coil, which the furnace blower sweeps before pushing the air into the ducts. In summer, a reversing valve flips the cycle and the heat of the house is rejected outdoors. The electric furnace itself changes nothing in how it works: its elements wait for the thermostat to call them.
Winter, with the furnace's electric auxiliary heat
The thermostat decides when the heat pump heats alone and when the furnace's electric elements come in as auxiliary heat. In fall, in spring and through a good part of winter, the heat pump is enough. When the cold becomes too sharp for it, the elements top up the heat. This pairing does not carry the cold-climate designation; in an ADD-ON system, the furnace's elements are precisely what covers the coldest nights.
In an electrically heated family home, those elements are among the largest loads of the winter: the longer the heat pump heats alone, the less they run. During defrost, they may heat for a few minutes so that the air from the grilles stays warm. The moment auxiliary heat comes in is set according to your house, its insulation and your comfort.
Summer in a family home
A family home builds up heat from several sources in summer: sun on the large windows, the kitchen, electronic devices. The heat pump cools every room served by the ducts, and the coil removes humidity from the air; the condensed water flows through a drain to a floor drain or a pump.
A finished basement needs little cooling but benefits from the drier air. The dampers on the grilles let you reduce the airflow there and send more to the bedrooms; we do this initial balancing at commissioning, avoiding fully closing too many grilles, which would starve the coil of the air it needs.
System ratings
The pairing of the N4H5S30AKAAA outdoor unit and the EVD4X30M17A 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 publishes no rating figure.
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.
The installation, from the basement to the yard
In the basement
The 17.5 in. coil is set on the furnace's air outlet and connected to the supply plenum. Its condensate drain is routed to a floor drain or a pump, with a steady slope. If a humidifier is mounted on the plenum, its location is reviewed, since the coil takes that spot. We also replace the thermostat: a thermostat made for an electric furnace alone cannot control a heat pump and its auxiliary heat, and we add, where needed, the wiring missing to the outdoor unit.
In the yard
The outdoor unit is installed on a bracket or a pad, above the snow line, away from roof drips, dryer vents and bedroom windows. Defrost water must drain without freezing on a driveway or a walkway, and the unit must remain accessible for maintenance. The insulated copper line runs to the coil; it is brazed, pressure tested and put under vacuum before the valves are opened. The unit gets a dedicated circuit and a nearby disconnect; we check that the panel can carry the heat pump in addition to the furnace's elements.
At commissioning, we check the refrigerant charge, airflow, defrost and the furnace's electric elements coming in, then we explain the thermostat to you.
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, without covering it in winter. 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 | 2.5 Tons - 30,000 BTU (Coil EVD4X 17.5 in.) - R410A. We assess the home room by room, measure the space for the coil and confirm the right size and your grant eligibility before signing.
Available while supplies last.