The kitchen is the worst room in which to install a wall-mounted head, and it is often the only possible one.
In a home without ductwork, the open main-floor area is almost always the primary zone to cool. And in most homes on the South Shore, that open area includes the kitchen. The head therefore spends eight hours a day breathing the air of a room where people fry, boil, and roast. No technical specification sheet mentions that.
This Boucherville project is a good example: the main head is recessed into the row of upper cabinets, below the ceiling, in an open kitchen. Boucherville has 42,067 residents spread across 71.16 km² of land, in the Longueuil agglomeration, in Montérégie. It is a city divided into nine sectors, with a dense single-family housing stock featuring renovated kitchens—and municipal regulations for air-conditioning equipment that are more specific than average, which we will revisit in the second half of this article.
The project at a glance
- Outdoor unit: GREE FreeMatch R32 GWHD(18)ND6MO, R32 refrigerant, G10 inverter technology
- Indoor heads: 12,000 BTU/h in the open kitchen–dining–living area and 9,000 BTU/h in the primary bedroom
- Installed capacity: 21,000 BTU/h of indoor heads on a nominal 18,000 BTU/h compressor, or 117%
- Efficiency: SEER2 21, HSPF2 10, EER2 12.5, EER 3.52, COP 3.9, ENERGY STAR certified
- AHRI codes: 214931586 (ductless), 214931591 (ducted), 214931592 (mixed)
- Electrical: 208/230 V, MCA 14.5 A, maximum overcurrent protection (MOCP) 20 A
- Outdoor unit: 822 × 550 × 352 mm, 35.5 kg, 54 dB(A), factory charge of 900 g of R32
- Piping: 6 m + 9 m = 15 m total developed length, versus a 10 m factory charge — 100 g of R32 added and weighed
- Electric baseboards retained throughout
Why the GWHD(18)ND6MO—and what comes with it
Two characteristics of this model deserve to be known before signing, because they are not apparent in a brochure skimmed quickly.
This model has no heating backup
It is the only model in the lineup in this situation. On the higher-end models, the maximum modulated heating capacity is well above the rated capacity: 30,000 BTU/h rated versus 40,900 maximum on one, 36,000 versus 51,180 on another, and 44,300 versus 54,590 on the largest. The GWHD(18), by contrast, specifies 18,000 BTU/h rated and 18,100 maximum modulated. In other words, there is no extra heating capacity to draw on when it gets cold.
We say this plainly because it changes a decision: this model is an excellent choice when the priority is summer comfort and supplemental heating in the fall and spring. It is not the right choice for someone hoping to eliminate their electric baseboards in January. The crossover point arrives sooner, the baseboards run for more days, and this is acknowledged in the project documentation rather than discovered during the first deep cold snap.
Its factory charge covers one-third the piping length of the larger models
The factory charge of the GWHD(18) covers 10 m of piping, compared with 30 m on the next model up and 40 to 50 m on the larger ones. In a real house, with two units in two different locations, you almost always exceed those 10 m. Here, 15 m of developed length required 100 g of added, weighed R32, which is neither serious nor unusual—but it must appear in the quote, actually be weighed on site, and be recorded, because the final charge determines the minimum room area associated with the R32 refrigerant. A quote that says nothing about the developed length for this model has not done the calculation.
What a unit breathes in a kitchen
The filter in a wall-mounted unit is a protective mesh for the heat exchanger. It stops hair, lint, and coarse dust. It does not stop aerosols.
Cooking grease passes through and condenses on the fins
Frying, sautéing, and roasting release fine oil droplets that remain suspended and rise. The intake grille of a wall-mounted unit is on top of the housing, a few centimeters from the ceiling—exactly where this plume accumulates. The droplets pass through the mesh and settle on the cold aluminum of the fin block.
Three consequences, in the order in which they appear:
- The buildup feeds itself. A greasy fin traps the dust that got past the filter, and the dust in turn traps the next layer of grease.
- Heat transfer drops before airflow does. An insulating film on the fin degrades heat transfer long before it visibly clogs anything. There is no fault code for a fouled heat exchanger.
- Rinsing the filter changes nothing. The finned coil is behind it. Cleaning it is a technical operation, and in a kitchen it may need to be done more frequently than annually. Soiling related to the operating environment is generally not covered by the warranty.
Steam is a load, not an odor
A boiling pot, a pasta colander being drained, and a dishwasher opening at the end of its cycle each release a significant amount of moisture at once, near the ceiling. In cooling mode, this is a spike in latent load arriving directly at the intake. The coil operates wetter, and the drain works harder. This is not a defect, but it is another reason why the drain should be checked under actual flow during commissioning, rather than simply inspected.
The range hood changes what the head receives
An effective range hood is an extractor. The air it exhausts outdoors must be replaced, and it enters through leaks in the home's envelope. In practical terms, as soon as the hood runs at high speed, the kitchen receives untreated outdoor air: humid and hot in July, cold in January. The head simply measures what is supplied to it.
What you should take away as a homeowner: if your kitchen becomes warm and clammy while you cook, despite a heat pump operating normally, the unit is probably not at fault. And if your home has a naturally vented combustion appliance, the question of make-up air goes beyond the scope of air conditioning and should be validated with the relevant trade professional—we do not settle it in an article.
A head recessed between two cabinets
The installation shown here places the head in the opening between two upper cabinets. It is aesthetically successful, and it requires three checks that we perform before fastening the plate.
- The manufacturer's side and front clearances, which are not symmetrical and can be compromised by cabinets deeper than the unit, redirecting discharged air toward the intake.
- The front panel opening, which swings upward on many models: clearance that complies on paper can make filter removal difficult, and maintenance that is difficult is maintenance that does not get done.
- The replacement envelope, and this is the point almost no one raises. In twelve or fifteen years, the unit will be replaced. A kitchen built to the millimetre around the dimensions of a 12,000 BTU/h head forces its successor to fit into the same niche. We therefore record the exact dimensions in the handover file, so the next technician does not have to dismantle cabinets.
The question of the patio door located beneath this unit—the open-door use, its latent load, and what it does to the compressor—belongs to another one of our projects, so we will not revisit it here.
Three Regulations for a Single Unit: What Boucherville Actually Requires
Boucherville is one of the municipalities that publish a page dedicated to air-conditioning units. This is good news for a homeowner: the rule is clear before choosing a location, not afterward.
A permit is required even for a wall-mounted unit or one on a balcony
This is the point that most often comes as a surprise. The City requires a permit to install an air-conditioning unit, heat-exchange unit, or ventilation equipment, whether installed on the ground, on a wall, or on a balcony. Many homeowners assume that a mounting on brackets or a balcony avoids the procedure because it does not touch the ground. In Boucherville, it does not.
Who Says What, and in Which By-law
The City refers to three separate texts, and that separation is what needs to be understood:
- By-law 2018-294, permits and certificates of authorization — sections 49 and 50, which determine which work requires a permit. This is the text that answers “do I need authorization?”
- By-law 2018-290, zoning — section 8-29, standards concerning the placement of accessory equipment. This is the text that answers “where is the unit allowed to be?”
- By-law 2008-112, nuisances — section 30, noise generated by air-conditioning equipment. This is the text that answers “under what conditions is it allowed to operate?”
We publish no clearances, distances, or decibel values here: these figures are set out in the regulations themselves, they change, and a two-year-old article that quotes them is more dangerous than one that refers readers to the text. They can be found in the PDFs published by the City or verified at the planning department counter.
A permit certifies a position, not peace and quiet
That is the practical consequence of this separation into three texts, and it is the trap into which otherwise well-executed projects fall.
The first two regulations result in a one-time authorization: you submit the application, demonstrate that the location complies, obtain the permit, and the file is closed. The third one never closes. The nuisance regulation governs the noise produced, meaning the unit's ongoing behavior, and it continues to apply every summer throughout its useful life.
A unit can therefore fully comply with zoning, have a valid permit, and still be the subject of a neighbor complaint two summers later—because a hedge has grown and reflects the sound, because a neighbor has built a patio on the unit’s side, or simply because night mode was never activated during commissioning. Compliance at the time of installation offers no protection afterward. That is why we treat airflow direction, clearance from reflective surfaces, and activation of night mode as design elements, not end-of-day adjustments.
The special case of Old Boucherville
The city states that special rules apply in Old Boucherville. We do not detail them here because we cannot quote the exact wording, but the practical implication is simple: for an address in this area, the question of placement should be addressed with the planning department before the model is ordered, not between delivery and installation.
Mistakes to avoid
- Assuming that a wall- or balcony-mounted installation is exempt from permitting.
- Checking the zoning and ignoring the nuisance bylaw, or vice versa.
- Choosing the airflow direction based on the façade rather than the neighbor.
- Leaving night mode disabled after commissioning.
- Cleaning the filter of a kitchen head and assuming the heat exchanger is clean.
- Recessing a head into cabinetry without recording its dimensions in the file.
- Accepting a quote that does not specify the developed length on a model whose factory charge covers only 10 m.
Eligibility for financial assistance
The FreeMatch R32 models are ENERGY STAR certified and eligible for local rebates; LogisVert and Rénoclimat are the programs to verify for a fully electric home. We publish no amounts: conditions change from year to year, and eligibility is verified when the file is opened, using the code for the configuration actually installed.
At AirGreen, we design, install, and service ductless systems in Boucherville, throughout the Longueuil agglomeration and across the South Shore, as well as in Montreal, Laval, and the North Shore. An HVAC installation in a kitchen is not judged during its first summer; it is judged during its third, when the unit is opened.