Installation of a GREE FreeMatch R32 2-Head Heat Pump in Saint-Marc-sur-Richelieu

When Only One Wall Is Available: Placing a Head Above a Patio Door

Houses and apartments built over the past twenty years have one thing in common that complicates our work: very large glazed areas and very few solid walls. The living room has a patio door across one entire façade, a large window on another, and a wall occupied by a fireplace or a bookcase. Often, only one surface remains capable of receiving a wall-mounted head: the strip of wall above the patio door.

In Saint-Marc-sur-Richelieu, this was exactly the configuration we encountered for this GREE FreeMatch R32 2-head wall-mounted heat pump. The head was installed in the space between the patio door lintel and the ceiling—a narrow area that requires precise checks before even drilling the first hole.

The Real Constraints of Installing Above an Opening

Available Clearance

The manufacturer requires minimum clearance between the top of the unit and the ceiling; without it, return air is restricted. The unit loses capacity, increases its fan speed to compensate, and becomes noisy. We measure this clearance before promising the client a location. When it is insufficient, we suggest another wall or another type of head—never a compromise on clearance.

The Lintel Structure

The wall above a patio door does not have the same framing as the rest of the room. The lintel and the short studs above it are not located where one might expect. The mounting plate must be anchored into wood, not drywall alone. A plate held by drywall anchors eventually shifts, putting stress on the piping connections and the drain line—this is a classic cause of an indoor water leak appearing two years after installation.

The Blind and Its Fabric

This is the detail that almost no one anticipates. A roller blind, valance, or curtain rod installed directly below the unit ends up directly in the path of the discharged air. Two consequences:

• The air is deflected toward the glazing instead of being projected into the room, wasting part of the system's capacity against the coldest surface in the house during winter;
• The blind vibrates or bangs at high fan speed.

We check the position of existing window coverings and the actual discharge-air angle before setting the height of the head. When a conflict is unavoidable, it is better to tell the client and agree on an adjustment to the blind than to let them discover it during the first heat wave.

Why This Location Still Works Very Well

Thermally, a patio door is the weak point of the room: this is where solar heat enters in summer and heat is lost in winter. Treating the air directly at this location offers a real advantage.

In cooling mode, the head intercepts solar heat at its source and prevents a hot zone from forming near the glazing. In heating mode, the downward-directed air creates a tempered-air curtain along the cold surface, eliminating the cold-wall sensation and the descent of cold air to the floor—the familiar draft felt by people sitting near a large window.

It is the same principle as electric baseboard heaters installed beneath windows, applied from above.

The Display, and What the Number Means

A display on the front of the head shows a number. Depending on the setting, it displays either the setpoint temperature or the room temperature measured by the internal sensor. This distinction causes a great deal of confusion.

Two points we explain systematically during commissioning:

1. The head's sensor reads the air at ceiling level, not at the level where occupants live. In heating mode, the difference can be significant if the louvers do not push the air downward. A system that appears to be “not heating” is very often a system whose louvers are incorrectly oriented.
2. The display can be turned off. In a bedroom, a constantly illuminated display can be bothersome. The function can be disabled with the remote control, and no one should have to live with a bright indicator above their bed simply because they did not know it could be turned off.

The Condensate Drain: The Question to Resolve First

A wall-mounted head produces condensate in cooling mode. The water must be drained by gravity, with a continuous downward slope all the way outside.

When the head is installed high on an exterior wall, gravity does the work. When the only available wall does not allow for a proper slope—an interior wall, a long route, or a structural obstacle—a condensate pump is required. This is a choice we address openly rather than forcing an insufficient slope:

• An approximate slope creates a flat spot where water stagnates, biological deposits form, and the drain eventually becomes blocked. The water then comes out through the head's drain pan and onto the wall.
• A properly installed pump permanently solves the problem, with a safety switch that stops the unit if the pan fills.

We test every drain by pouring water into the pan and confirming complete drainage outside. This is a five-minute step that many contractors skip.

The Installed System

The GREE FreeMatch R32 in a dual-zone configuration supplies two indoor heads from a single outdoor unit, a single 208/230 V electrical circuit, and a single wall penetration.

What matters to a client in Quebec:

• SEER2 21 / HSPF2 10 / EER2 12, certified by AHRI and ENERGY STAR Cold Climate;
• Heating maintained down to -30 °C, with intelligent defrost and self-diagnostics;
• R32 refrigerant, A2L safety classification, with low global warming potential;
• G10 inverter enabling operation at partial load for most of the season instead of a succession of starts and stops;
• 10-year warranty on parts and the compressor, with an additional 2 years upon registration.

The transition to R32 adds a design check: because this refrigerant is classified as A2L, there is a minimum room area based on the system charge and installation height. A high-capacity head in a small enclosed room is not always permissible. This calculation is performed before installation, never afterward.

The Mistakes We Correct Most Often

1. Oversizing. An oversized system cycles off too quickly, no longer dehumidifies properly in summer, and loses the benefit of modulation in winter. We size systems based on floor area, insulation, orientation, and especially glazed areas—a room with a large south-facing patio door does not have the same load as an identical north-facing room.
2. Treating R32 like R410A. Nitrogen-purged brazing, deep vacuum evacuation, and documented leak testing: A2L protocols are not optional.
3. Skipping commissioning. Without documented initial pressure and temperature readings, no technician will be able to determine four years later whether the system has drifted.
4. Neglecting the filters. Cleaning every four to six weeks maintains airflow and therefore capacity. This is the leading cause of service calls we receive.

Rebates

The FreeMatch R32 is certified by ENERGY STAR, Cold Climate, and AHRI, making it eligible for the categories targeted by Quebec assistance programs for efficient heating systems. The AHRI number applies to the combination of the outdoor unit and indoor heads, never to the outdoor unit alone. We validate this combination before signing—the financial assistance cannot be claimed retroactively.

Our Service Area

At AirGreen, we handle complete HVAC installation: load calculation, selection of the certified combination, indoor and outdoor installation, documented commissioning, and annual HVAC maintenance. We serve Montreal, Laval, Longueuil, the North Shore, the South Shore, and Montérégie, including Saint-Marc-sur-Richelieu and the Richelieu Valley. When only one wall is available, the job is to make the most of it without sacrificing any installation requirements.