{"product_id":"thermopompe-centrale-add-on-arcoaire-r4h5s-economique-3-5-tonnes-42000-btu-serpentin-evd4x-17-5-po-r410a","title":"Central Heat Pump ADD-ON ARCOAIRE R4H5S Economy | 3.5 Tons - 42,000 BTU (Coil EVD4X 17.5 in.) - R410A","description":"\u003ch2\u003eKeep what works in the house and add what is missing\u003c\/h2\u003e\u003cp\u003eThe 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 \u003cstrong\u003eCentral Heat Pump ADD-ON ARCOAIRE R4H5S Economy | 3.5 Tons - 42,000 BTU (Coil EVD4X 17.5 in.) - R410A\u003c\/strong\u003e pairs the \u003cstrong\u003eR4H5S42AKAAA\u003c\/strong\u003e outdoor unit with the \u003cstrong\u003eEVD4X42M17A\u003c\/strong\u003e coil.\u003c\/p\u003e\u003cp\u003eThe ADD-ON starts from a simple observation: in many homes, the \u003cstrong\u003eelectric furnace\u003c\/strong\u003e and the \u003cstrong\u003educts\u003c\/strong\u003e still have good years ahead of them. It would be a shame to replace them only to get air conditioning and more efficient heating. This pairing adds a \u003cstrong\u003ecentral heat pump\u003c\/strong\u003e to the existing system and leaves in place everything that is still in good condition.\u003c\/p\u003e\u003ch3\u003eWhat you keep\u003c\/h3\u003e\u003cul\u003e\u003cli\u003e\u003cstrong\u003eThe electric furnace\u003c\/strong\u003e, whose heating elements become the backup for the coldest days.\u003c\/li\u003e\u003cli\u003e\u003cstrong\u003eThe duct system\u003c\/strong\u003e, the supply registers and the return air grilles.\u003c\/li\u003e\u003cli\u003e\u003cstrong\u003eThe filter rack\u003c\/strong\u003e and the filter format you already know.\u003c\/li\u003e\u003cli\u003e\u003cstrong\u003eAccessories\u003c\/strong\u003e connected to the furnace, such as a humidifier, in most cases; we check their position relative to the coil.\u003c\/li\u003e\u003cli\u003e\u003cstrong\u003eThe thermostat location\u003c\/strong\u003e, even though the device itself changes.\u003c\/li\u003e\u003c\/ul\u003e\u003ch3\u003eWhat the installation adds\u003c\/h3\u003e\u003cul\u003e\u003cli\u003eThe \u003cstrong\u003eR4H5S42AKAAA\u003c\/strong\u003e outdoor unit, on a stand above the snow line.\u003c\/li\u003e\u003cli\u003eThe \u003cstrong\u003eEVD4X42M17A\u003c\/strong\u003e coil, a \u003cstrong\u003e17.5 in.\u003c\/strong\u003e format, placed on the furnace's air outlet.\u003c\/li\u003e\u003cli\u003eAn insulated \u003cstrong\u003erefrigerant line set\u003c\/strong\u003e between the outdoor unit and the coil.\u003c\/li\u003e\u003cli\u003eA \u003cstrong\u003econdensate drain\u003c\/strong\u003e to the floor drain or a pump.\u003c\/li\u003e\u003cli\u003eA \u003cstrong\u003ededicated circuit\u003c\/strong\u003e and an outdoor disconnect.\u003c\/li\u003e\u003cli\u003eA \u003cstrong\u003eheat pump thermostat\u003c\/strong\u003e that controls the heat pump and brings in the furnace's electric elements as \u003cstrong\u003eauxiliary heat\u003c\/strong\u003e.\u003c\/li\u003e\u003c\/ul\u003e\u003cp\u003eIf an old central air conditioner already had its coil and line set, we assess what can be kept. The coil itself is replaced, since it must now work in heating as well as cooling.\u003c\/p\u003e\u003ch3\u003eThe furnace: what we check before proposing an ADD-ON\u003c\/h3\u003e\u003cp\u003eAn ADD-ON is only worthwhile if the furnace that goes with it is reliable. During the visit, we examine:\u003c\/p\u003e\u003cul\u003e\u003cli\u003ethe age and general condition of the furnace, along with its maintenance history;\u003c\/li\u003e\u003cli\u003ethe width of the cabinet, to match it to the 17.5 in. coil;\u003c\/li\u003e\u003cli\u003ethe blower: type of motor, speeds available and ability to deliver the airflow the coil requires;\u003c\/li\u003e\u003cli\u003ethe clearance above the furnace, since the coil fits between the air outlet and the plenum;\u003c\/li\u003e\u003cli\u003ethe condition of the heating elements and their connections, and the compatibility of the furnace control with a heat pump thermostat that manages auxiliary heat.\u003c\/li\u003e\u003c\/ul\u003e\u003ch3\u003eWhen an ADD-ON is not the right choice\u003c\/h3\u003e\u003cp\u003eWe sometimes advise against this type of installation. A furnace at the end of its life, a blower unable to deliver the required airflow or a duct system too small for air conditioning turn a simple addition into a series of compromises. In those cases, a \u003cstrong\u003ecentral heat pump\u003c\/strong\u003e paired with a new air handler, which replaces the furnace, is often the most sensible long-term solution.\u003c\/p\u003e\u003cp\u003eIf the furnace shows signs of advanced wear, such as heating elements that keep failing, electrical connections that have overheated or a tired blower, it is better to settle that question before adding anything to it. We would rather tell you during the visit than install a new coil on equipment that will need replacing shortly after.\u003c\/p\u003e\u003ch3\u003eThe Economy series\u003c\/h3\u003e\u003cp\u003eThe name Economy designates the series of the \u003cstrong\u003eR4H5S42AKAAA\u003c\/strong\u003e unit in the Arcoaire lineup. The \u003cstrong\u003eEVD4X42M17A\u003c\/strong\u003e coil is the same as in the other series of this size; it is the outdoor unit that changes. In an ADD-ON, the furnace's electric elements handle the coldest days: the heat pump concentrates on summer cooling and on heating in the shoulder seasons, and the choice of series becomes a matter of priorities.\u003c\/p\u003e\u003cp\u003eThe series name does not tell the whole story, though. What counts are the ratings of the pairing, and we confirm them before the quote.\u003c\/p\u003e\u003ch3\u003eSystem ratings\u003c\/h3\u003e\u003cp\u003eThe pairing of the \u003cstrong\u003eR4H5S42AKAAA\u003c\/strong\u003e outdoor unit and the \u003cstrong\u003eEVD4X42M17A\u003c\/strong\u003e 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.\u003c\/p\u003e\u003cp\u003eThis page therefore shows no efficiency rating. The confirmed ratings, provided in writing, let you compare this series with the other options of the same size on a concrete basis.\u003c\/p\u003e\u003ch3\u003eThe 3.5-ton size\u003c\/h3\u003e\u003cp\u003eThis size often suits a family home of good size: a two-storey house with a finished basement in \u003cstrong\u003eLaval\u003c\/strong\u003e, a split-level on the \u003cstrong\u003eSouth Shore\u003c\/strong\u003e, an extended bungalow. These examples are only a guide, since insulation, windows and airtightness change the load. Because the furnace's electric elements cover the deep cold, we size the heat pump on the cooling load, established by a room-by-room \u003cstrong\u003eload calculation\u003c\/strong\u003e: an oversized unit cools in short cycles and dries the air poorly.\u003c\/p\u003e\u003ch3\u003eWinter and summer, day to day\u003c\/h3\u003e\u003cp\u003eIn mild and cool weather, the heat pump heats alone. When the cold deepens and it can no longer keep up, the \u003cstrong\u003ethermostat\u003c\/strong\u003e brings in the furnace's electric elements as \u003cstrong\u003eauxiliary heat\u003c\/strong\u003e; in deep cold, they carry the heating. The point at which the backup comes in is set according to the heat loss of the house and your preferences; we set it at commissioning. The air delivered by the heat pump is less hot than the air from the electric elements and the cycles are longer: this is normal. During defrost cycles, a plume of vapour comes out of the outdoor unit, and the furnace's elements may come on briefly to keep the supply air comfortable.\u003c\/p\u003e\u003cp\u003eIn summer, the same unit cools the whole house through the existing ducts. The coil removes humidity from the air, and the water goes to the condensate drain. If the upper floor stays warmer than the main floor, we look at register balancing and return air during the visit.\u003c\/p\u003e\u003ch3\u003eLogisVert\u003c\/h3\u003e\u003cp\u003eThis 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.\u003c\/p\u003e\u003ch2\u003eInstallation on the existing furnace\u003c\/h2\u003e\u003cp\u003eThe 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 \u003cstrong\u003ededicated circuit\u003c\/strong\u003e.\u003c\/p\u003e\u003cp\u003eOn site, the order of work stays the same: installation of the coil and drain, installation of the stand and outdoor unit away from roof drip, routing of the line set, electrical connection, then commissioning with a nitrogen pressure test, vacuum, and adjustment of the \u003cstrong\u003eR-410A\u003c\/strong\u003e charge, the airflow and the thermostat's auxiliary heat setting.\u003c\/p\u003e\u003ch3\u003eMaintenance\u003c\/h3\u003e\u003cp\u003eReplace the system filter according to its format, keep the outdoor unit clear of snow and leaves, and plan annual \u003cstrong\u003eHVAC maintenance\u003c\/strong\u003e of the coil, condensate drain and electrical connections. In winter, white vapour during defrost is normal.\u003c\/p\u003e\u003cp\u003eThe filter stays where it was, at the furnace inlet. It now also protects the coil: a clogged filter reduces the airflow and the capacity of the system, summer and winter. The electric furnace keeps its usual maintenance, centred on the blower, the heating elements and their connections.\u003c\/p\u003e\u003ch3\u003eAirGreen, for the life of the installation\u003c\/h3\u003e\u003cp\u003eA family business active for more than fifteen years in \u003cstrong\u003eMontreal\u003c\/strong\u003e, \u003cstrong\u003eLaval\u003c\/strong\u003e, \u003cstrong\u003eLongueuil\u003c\/strong\u003e, the \u003cstrong\u003eNorth Shore\u003c\/strong\u003e and the \u003cstrong\u003eSouth Shore\u003c\/strong\u003e, we hold RBQ licences for ventilation, refrigeration and electrical work and carry \u003cstrong\u003e$5,000,000\u003c\/strong\u003e in liability insurance. The in-home assessment is free, the quote is in writing, and our \u003ca href=\"\/en\/pages\/financement-avec-financeit\"\u003efinancing options\u003c\/a\u003e let you choose the right unit rather than the cheapest one.\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eRequest your free estimate for the Central Heat Pump ADD-ON ARCOAIRE R4H5S Economy | 3.5 Tons - 42,000 BTU (Coil EVD4X 17.5 in.) - R410A. We assess the home room by room and confirm the right size and your grant eligibility before signing.\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eAvailable while supplies last.\u003c\/strong\u003e\u003c\/p\u003e\u003cp\u003e\u003cstrong\u003eWarranty:\u003c\/strong\u003e 10 years on the compressor, 10 years on parts and 6 years on labor.\u003c\/p\u003e","brand":"Arcoaire","offers":[{"title":"Default Title","offer_id":67799184998692,"sku":"R4H5S42AKAAA","price":0.0,"currency_code":"CAD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0715\/1694\/6724\/files\/THERMOPOMPE_CENTRALE_ADD_ON_ARCOAIRE_R4H5S_3_5_TONNES_42000_BTU_R410A_00_MONTREAL_LAVAL_LONGUEUIL_RIVE_SUD.png?v=1793082540","url":"https:\/\/airgreen.ca\/en\/products\/thermopompe-centrale-add-on-arcoaire-r4h5s-economique-3-5-tonnes-42000-btu-serpentin-evd4x-17-5-po-r410a","provider":"AirGreen Climatisation \u0026 Chauffage \/ Air Conditioning \u0026 Heating","version":"1.0","type":"link"}