Installation of a GREE FLEXX R32 electric furnace in Sainte-Anne-de-Sabrevois (Haut-Richelieu RCM, Montérégie)

The photo taken at 2 p.m., at the exact moment when the house has no heat at all

There is a moment during every conversion from an electric furnace to a central heat pump system when the house is completely without heat. The old unit is gone, the new one is standing but silent, the conductors hang along the cabinet without being connected, and there are still a few hours left in the day.

That is exactly what the photo from this Sainte-Anne-de-Sabrevois job shows. A GREE FLEXX R32 cabinet installed in a basement corner, the sheet metal assembled, the red, black, and white conductors still loose at the exit of the armored cable, a tool bag on the floor, and an extension cord running across the room.

At AirGreen, we rarely document this moment because it is not particularly flattering. Yet it is what distinguishes an organized team from one that improvises. Here is what a conversion day actually looks like, from the truck parked in the morning to the readings handed over to the customer in the evening.

The context: a Haut-Richelieu bungalow and a 90-centimeter basement corner

Sainte-Anne-de-Sabrevois is a municipality along the Richelieu River, in the Haut-Richelieu, with a housing stock dominated by bungalows and single-story homes built between 1960 and 1990. The area has no natural gas: heating is electric, and nearly all homes equipped with a duct system operated with a vertical electric furnace.

The house on this job followed the pattern. The distribution network was sound, the return air passed through a wall grille and a horizontal main running along the basement wall, and the old unit occupied a corner directly beside the cold-room door.

This location created the day's main constraint: the unit is accessible from only one side. On the left, the cold-room door frame. On the right, the return-air plenum. Behind it, the wall. Everything that will need to be serviced, measured, or replaced over the next fifteen years will have to be done from the front.

The installed equipment and its certified data

The selected configuration is a 2-ton GREE FLEXX R32:

• Indoor unit (ventilation cabinet): GUD24AH2/G-D(U)
• Outdoor unit: GUD36W2/NhE-D(U)
• AHRI number : 217120759
• Cooling capacity: 24,000 BTU/h nominal, modulation from 12,000 to 30,000 BTU/h
• Heating capacity: 23,000 BTU/h nominal, modulation from 12,000 to 30,000 BTU/h
• TRÉS2 (SEER2) : 18 — CPSC2 (HSPF2) : 10
• TRÉ2 (EER2): 12.5 and COP of 3.6, the two best instantaneous ratings in the FLEXX range
• Refrigerant: R32, factory charge of 2.5 kg, the lowest in the range
• Heating range: -30 °C to 24 °C — Cooling range: -15 °C to 54 °C
• Cabinet dimensions: 18 1/8 x 43 1/2 x 21 1/4 in. (460 x 1105 x 540 mm), making it the narrowest cabinet in the range
• Weight: 61.5 kg for the indoor unit
• Power supply: 208–230 V, MCA of 4.7 A and MOCP of 15 A for the indoor cabinet
• Outdoor unit : MCA of 27.7 A and MOCP of 30 A
• ENERGY STAR certification, A2L leak-detection sensor included, factory-installed Wi-Fi, controlled by a conventional 24 VAC thermostat

The cabinet's 46 cm width is not a minor detail on this job: it made it possible to preserve clearance around the cold-room door frame without rebuilding the corner.

The actual sequence of a conversion day

7:30 a.m. — Surface protection and measurements before any dismantling

Before a single tool comes out, two things are done.

The first is protection: drop cloths on the staircase and corridor floors, threshold protection, and clearing the work area. A finished basement is not a construction site, and it should not look like one at the end of the day.

The second is documenting the existing setup: exact plenum dimensions, return-air position, available height, electrical-circuit routing, and conductor ampacity. A team that takes these measurements on the morning of installation has already made an upstream error; these measurements are taken during the technical visit, and those taken that morning only serve to confirm them.

8:30 a.m. — Refrigerant recovery and removal of the old unit

When converting from a pure electric furnace, there is no refrigerant to recover: the power is disconnected, the sheet-metal connections are dismantled, and the cabinet is removed. When an old central air conditioner is present, its charge must be recovered into a recovery cylinder by a certified technician before any dismantling and transported to a processing facility. This step is not optional.

The old unit exits via the same staircase the new one will use, which provides a useful indication: if the old one came out without forcing, the new one will fit.

10 a.m. — Positioning in a corner accessible from only one side.

It is the decision with the greatest consequences of the day, and it takes only a few minutes.

The unit is placed on its base, leveled in both directions, and above all oriented. The fan access panel, electrical panel, and filter drawer must all face the only open space. A 90-degree rotation that seems harmless at 10 a.m. turns every future service call into a plenum removal.

On this job, the cabinet was positioned so that the walk-in cooler door could continue to open fully and the front of the unit would remain completely clear.

11:30 a.m. — The sheet metalwork built on site

No existing ductwork matches a new unit's dimensions exactly. The transitions visible in the photo—the supply plenum to the ceiling trunk, and the side connection to the return—were fabricated and installed on site.

Three rules govern this work:

1. Gradual transitions. An abrupt change in section creates pressure loss and a whistling sound that the customer will hear every evening.
2. Complete sealing, at both the joints and the cleats. Air leaking into a basement is heated or conditioned air paid for nothing.
3. Removable sections at strategic locations, so a future replacement will not require cutting the sheet metal with a grinder.

1 p.m. — The refrigerant line

The line connects the outdoor unit to the cabinet. In this configuration, the diameters are 3/8 in. for the liquid line and 3/4 in. for the gas line, the precharged length is 7.5 m, and the additional charge beyond that is 30 g per meter. The maximum length between the units is 30 m, with a maximum elevation difference of 15 m.

Brazing is performed under a flow of nitrogen, the system is pressurized for the leak test, and the fittings are continuously insulated. Since R32 is a refrigerant A2L, the tools and handling procedures are subject to requirements specific to this classification.

2 p.m. — The electrical connection: the moment of the photo

This is the moment captured in the image. The armored cable descends from the ceiling, enters the unit through an approved connector, and the power conductors are ready for connection. The thermostat wire follows a separate route.

Four points are checked at this stage:

• The separation between the power conductors and the Class 2 control circuit.
• The cable clamp at every entry point, and a drip loop before the entrance.
• Tightening the terminals to the prescribed values. An insufficiently tightened terminal overheats, while an overtightened terminal strains the conductor.
• Matching the rating to the MCA and MOCP of each component: 4.7 A and 15 A for the cabinet, 27.7 A and 30 A for the outdoor unit, plus the dedicated circuit for the electric-heating kit.

At this time of day, the house is cold and the customer often watches over the technician's shoulder. That's normal, and it's the right time to explain what remains to be done.

3:30 p.m. — Evacuation and decay test

The system is evacuated to a deep vacuum with a suitable pump, measured with a micron gauge rather than an analog gauge, which is physically incapable of measuring a vacuum. Once the target is reached, the pump is isolated and the reading is monitored: a stable value confirms a dry, leak-free circuit.

The charge is then released, topped up as needed by weight, and recorded on a label affixed to the appliance.

5 p.m. — Commissioning, adjustments, and delivery of the readings

The day ends with the checks that determine performance for the next fifteen years:

• Configuring the 24 VAC thermostat in heat-pump mode with auxiliary heat, checking the reversing-valve polarity, and setting the electric auxiliary-heat lockout.
• Measuring airflow and static pressure on both sides of the appliance.
• Checking the temperature rise across the integrated electric furnace.
• Testing the defrost cycle and recovery.
• Checking the condensate and trap drainage.
• Checking the A2L sensor operation.

These values are recorded and given to the customer. Without them, no future diagnosis has a reference point.

The adjacent cold room: a local detail that matters

The cold rooms in Haut-Richelieu bungalows are vented outdoors and remain cold and damp year-round. When an HVAC appliance is installed right next to one, two checks are essential:

• No uninsulated duct should pass through this space. Heated air flowing through it condenses on the sheet metal, and water eventually appears on the basement ceiling.
• The door must remain airtight and closed. An open cold room turns the mechanical area into a cold zone and skews the return-air reading.

Mistakes to avoid during a one-day conversion

1. Starting without confirming that all parts are available. A missing transition at 3 p.m. turns one day into two, and the house spends the night without heat.
2. Positioning the unit without considering service access. This cannot be reversed without dismantling the sheet metal.
3. Reusing an existing, poorly matched transition because it is already in place.
4. Skipping airflow and static-pressure measurements because the day is long.
5. Charging the system without a scale, relying on pressure alone.
6. Leaving without explaining the supply-air temperature in heat-pump mode to the customer. The air comes out at around 32 to 38 °C rather than 45 to 50 °C, and this change must be explained, not discovered.
7. Failing to properly recover the refrigerant from an old air-conditioning unit.

Eligibility for rebates

The GREE FLEXX R32 is ENERGY STAR certified, and each indoor-outdoor pairing has its own AHRI number. For the configuration installed here, it is 217120759.

It is this number, not the name of the product line, that government programs and distributors require to validate eligibility for applicable rebates. Criteria and amounts change over time: we verify the eligibility of the exact matched system before the contract is signed and provide the AHRI certificate with the invoice.

What the Sainte-Anne-de-Sabrevois installation day illustrates

A successful conversion does not depend on the unit. It depends on a series of decisions made between 7:30 a.m. and 5 p.m., most of which cost nothing when they are made but become very expensive to correct later. The orientation of the cabinet in a corner accessible from only one side, the quality of the transitions fabricated on site, the separation of the circuits, the weighed charge, and the recorded readings.

At AirGreen, we install and service HVAC systems in Sainte-Anne-de-Sabrevois, throughout the Haut-Richelieu RCM and Montérégie, as well as in Montreal, Laval, Longueuil, on the North Shore, and on the South Shore. Our teams protect surfaces, properly recover old refrigerants, measure airflow and static pressure, weigh the refrigerant charge, and provide written commissioning readings.

For an assessment of your home and a detailed quote on a GREE FLEXX R32 central system with electric backup heat, contact our team. We come to take measurements, plan the day before starting it, and explain every step to you.