Installation of a GREE FreeMatch R32 2-head heat pump in Saint-Bernard-de-Lacolle

Cooling an entire floor from the corridor: what works and what you need to know before accepting it

In a two-story house, the problem is always the same: the ground floor is comfortable and the upper floor is unbearable from June to September. Warm air rises through the stairwell, accumulates beneath the roof, and the bedrooms become places where it is difficult to sleep.

At Saint-Bernard-de-Lacolle, we installed a GREE FreeMatch R32 2-head wall-mounted heat pump in this type of family residence. The head shown in the photo is mounted on the landing wall, between two bedrooms, above the open stairwell. This is a location we often recommend—but only after frankly explaining to the client what it does and does not provide.

Why the landing rather than a bedroom

The stairwell is a thermal chimney

Warm air from the ground floor rises through the staircase and spills onto the landing. By treating the air directly there, the head intercepts this mass of warm air at its point of arrival, before it spreads into the bedrooms. A head placed at the back of a single bedroom does nothing of the sort: it cools that room and leaves the rest of the floor to fend for itself.

One unit serves several rooms

A landing open to two or three bedrooms allows a single head to condition the entire floor, provided the air circulates. This is what makes a bi-zone configuration relevant for an entire house: one head for the upper floor and one head for the open area on the ground floor.

No noise in the bedrooms

Even when quiet, a head produces noticeable air movement. Installed in a corridor rather than above a bed, it disappears from the field of perception at night. This is an argument clients appreciate once summer arrives.

The limitation that must be stated: the doors being closed

Here is what an honest contractor should say before signing. A head mounted on the landing cools the floor as long as the air circulates. With the doors closed, it cools the corridor.

Many families close bedroom doors at night — for noise, privacy, or because a young child is sleeping. In that case, the bedroom becomes isolated from the only source of conditioned air, and its temperature gradually rises.

The solutions, in order of effectiveness:

1. Leave the doors ajar at night. Free, and sufficient in many cases.
2. Clear the bottoms of the doors. A gap of a few centimeters beneath the door allows minimal air transfer.
3. Install transfer grilles above doors or in partition walls. An effective, discreet solution, but one that also transmits noise.
4. Plan for a dedicated head in the primary bedroom when nighttime comfort is a priority. This is a design choice to make when calculating the load, not afterward.

We prefer to explain this before the work begins rather than receive a call in July. An informed client is a satisfied client; a surprised client never is.

The ceiling fan: an ally when it rotates in the right direction

The photo shows a ceiling fan above the landing. When used correctly, it doubles the perceived effectiveness of the heat pump.

• In summer, the fan blows downward. The air movement increases skin evaporation and makes it feel several degrees cooler, allowing you to raise the system's setpoint without sacrificing comfort.
• In winter, it should rotate in reverse at low speed. It then brings the warm air accumulated at the ceiling back down without creating a draft. In an open stairwell, this destratification is particularly useful — that is exactly where heat gets trapped.

Nearly all fans have a reversing switch on the housing. Almost no one uses it.

Airflow direction in a space open on three sides

A landing with an open stairwell presents a particular problem: some of the blown air may fall directly into the stairwell and descend to the ground floor, where it was not intended to go.

We therefore direct the airflow along the corridor, toward the bedroom doors, rather than into the open stairwell. The louvers are also adjusted differently depending on the season: horizontal airflow in cooling mode, so that the cold air naturally descends while circulating throughout the entire volume; downward airflow in heating mode, to push the heat toward the floor instead of letting it stagnate at the ceiling.

A system that “doesn’t heat” is very often one whose louvers were never redirected in the fall.

The maintenance detail we check before choosing the height

An indoor unit requires filter cleaning every four to six weeks. This is the most common reason for service calls we receive: a dirty filter reduces airflow, which reduces capacity and efficiency.

But an indoor unit mounted high above a stairwell cannot be accessed with a kitchen chair. We take this into account when determining the height and lateral position: the homeowner must be able to open the front panel and remove the filters from a stable footing, without placing a stepladder on a stair tread. When access is necessarily difficult, we say so and include cleaning in the annual HVAC maintenance contract rather than leaving it to the customer.

The upstairs condensate drain

An indoor unit produces condensate in cooling mode, and drainage relies on gravity. Upstairs, there are two possible situations:

• The unit is mounted on an exterior wall: the drain exits directly, with a clear slope. This is the ideal situation.
• The unit is mounted on an interior wall, such as a hallway wall: the drain must run through the structure for some distance before reaching the exterior. This requires a continuous slope along the entire route, without a single flat spot.

A drain that rises two centimetres somewhere inside an upper-floor wall is a leak waiting to happen — the water will eventually come back out through the indoor unit’s pan and run down the wall, one floor above the living room. When a slope cannot be guaranteed, we install a condensate pump with a safety switch that shuts the unit off if the pan fills. It is a cost we accept, not a compromise.

We test every drain by pouring water into the pan and confirming that it drains completely outside.

The installed system

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

What matters for a family in Quebec:

• SEER2 21 / HSPF2 10 / EER2 12, certified 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, which allows operation at partial load for most of the season instead of a succession of starts;
• Automatic voltage adaptation, useful in rural areas where the power supply fluctuates more;
• 10-year warranty on parts and the compressor, with 2 additional years upon registration.

Because R32 is classified as A2L, a minimum room area applies to each head based on the served load and mounting height. For a head installed in an open hallway overlooking a staircase, the available volume is generous; for a head being considered for a small enclosed bedroom, the verification may change the permitted capacity. This calculation is performed during the design stage.

Rebates

The FreeMatch R32 is certified ENERGY STAR, Cold Climate, and AHRI, making it eligible for the categories covered 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 the combination and eligibility before signing.

Our service area

At AirGreen, we provide 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, as far as Saint-Bernard-de-Lacolle and the border. On a floor of a family home, the right location is not chosen at random—it is chosen based on how the family actually lives in the house.