Installation of a Sharp ZU1 series (R-32) wall-mounted heat pump in Île-des-Sœurs
On a balcony on Nuns' Island , we are installing a Sharp ZU1 series (R-32) wall-mounted heat pump : raised support, anti-vibration, discreet cover and precise commissioning. An AirGreen HVAC installation designed for Montreal winters.
In summer, the outdoor unit rejects the house's heat outside.
Generic illustration of this type of installation, not a survey of this job site. Tap a number.
Mounted level on a wall plate, high enough for the air to reach the whole room, with enough space around it to slide the filters out easily.
The refrigerant lines, the communication cable and the drain go through the wall in a single opening, sealed against water, cold air and insects.
Two insulated copper pipes connect the two units. Outside, a line cover can protect them from sun, knocks and weather.
A shut-off switch near the outdoor unit isolates it safely for service. It must stay accessible at all times.
The compressor and the fan. In heating mode it captures heat from the outdoor air, even in winter, and moves it inside.
On the ground or on the wall, it keeps the unit above accumulated snow. The unit stays clear and defrost water can drain away.
The fan needs to blow freely. Storage, a fence or a wall too close, and efficiency drops while noise goes up.
Wind-exposed balcony, meticulous finishing and extreme cold performance: a condo moves to four-season comfort without compromise
Context: Responding to Nuns' Island's windy winters
At AirGreen , we are modernizing a condo on Nuns' Island with a Sharp ZU1 series (R-32) wall-mounted heat pump. The objective: to stabilize the temperature of the living room adjoining the sliding window, limit noise pollution on the facade and ensure reliable heating down to very low temperatures . The installation is carried out on a tiled balcony , in winter with snow on the ground, which guides our technical choices: elevation , frost management , air clearances and sealing of openings .
Why Sharp ZU1 series (R-32) for this condo
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Four-season efficiency : Sharp's recent R-32 ranges maintain high heating efficiencies in sustained cold while remaining economical in summer air conditioning .
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Silence and comfort : inverter compressor, anti-vibration strategy, progressive ventilation → low noise level outside and inside.
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Environmentally friendly : R-32 reduces the climate footprint compared to older generations of R-410A.
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Compactness : mini-split format ideal for condos and plexes in Greater Montreal , without heavy duct work.
Sizing: For a typical condo living area, we validate a range of 9,000 to 15,000 BTUs depending on the orientation, the envelope, and internal contributions. This calculation eliminates oversizing, which is detrimental to comfort and savings.
Reading the site: key clues and constraints
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Light-colored rendered facade and blue joinery typical of condominium buildings on Nuns' Island.
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Tiled balcony exposed to the wind, metal railing : open environment requiring controlled wind resistance .
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Outdoor unit on raised aluminum support , blue anti-vibration pads visible under the base.
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Electrical disconnect box in the immediate vicinity for emergency shutdown and maintenance.
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Short refrigeration connection entering perpendicular to the wall, insulated, with discreet cover up to the point of penetration.
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Snow on the ground : obligation to clear the air discharge and maintain a free path for de-icing water .
Our installation method (AirGreen process)
1) Preparation and clean drilling
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Identification of the refrigeration passage + communication + drain for the shortest possible crossing between the interior head and the condenser.
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Coring in the wall with sleeve, controlled slope for gravity flow and exterior sealing with elastomeric mastic; vapor barrier inside for continuity of the envelope.
2) Installation of the raised outdoor unit
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Level the support (≈ 40–50 cm from the tiles) to allow defrost water to pass through and prevent any accumulation of snow under the appliance.
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Respect clearances : front face free over 60–90 cm, rear and sides clear for optimal airflow .
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Stainless steel fixings and anti-vibration interface to prevent noise transmission to the balcony slab.
3) Refrigeration and electrical connections
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Bending of insulated copper tubes without wrinkles, clean nitrogen brazing , deep vacuum and micron leak testing .
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Power supply on dedicated circuit with circuit breaker rating in accordance with Sharp recommendations; installation of the watertight disconnection box with service clearances.
4) Commissioning and configuration
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Reading of pressures , suction/discharge temperatures , compressor current and superheat .
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Setting the modes and the fan curve , explanation of the defrost cycles for winter use.
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HVAC maintenance tips: filter cleaning, cowling inspection, seasonal check-up.
Visible details and justified choices
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Aluminum support : resistant to salt and frost, it prevents rapid corrosion often observed on exposed balconies.
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Blue pads : anti-vibration elements that reduce structural hum in the slab; noticeable effectiveness at the end of the evening.
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Discreet cover : protection of connections against UV and abrasion; neat aesthetics on the front.
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External sectioning : safety and compliance, particularly appreciated by co-ownership syndicates for rapid interventions .
Best practices for a balcony exposed to the wind
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Elevate the unit and keep the bottom clear for water drainage during defrost cycles.
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Avoid storing objects in front of the blower grille during the winter.
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Clear snow after storms to preserve airflow and heating capacity .
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Check the support base , the tightening torque and the condition of the anti-vibration pads annually.
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Schedule HVAC maintenance in the spring: cleaning the battery, checking pressures and the hood .
Results obtained
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Stable heating of the living room with a reduced temperature delta near the bay windows.
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External noise contained thanks to the separation of the support and inverter modulation.
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Clean finish , visually integrated with the light facade and railing.
Grants and Eligibility
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New generation R-32 wall-mounted heat pumps with high efficiency and capacity maintenance at −25°C/−30°C are often eligible for assistance programs available in Quebec. We confirm eligibility at the time of submission based on power (BTU) , performance testing and current administrative criteria.
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On the Island of Montreal, we support the customer throughout the process (certificates, installation photos, serial numbers), for a seamless experience from request to payment.
Alternatives according to housing in Greater Montreal
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Larger open area : increase in BTU or switch to a Multi-Zone Heat Pump if several rooms need to be treated.
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North Shore/South Shore/Laval houses : same standards, with snow guards or bases adapted to parking spaces and flat roofs.
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Acoustic constraints in co-ownership: addition of specific silent blocks , adjustment of minimum night speeds.
Maintenance and longevity: our owner checklist
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Keep 60–90 cm free in front of the blower front.
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Clean the inner head filters every 4 to 8 weeks during use.
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Inspect the cover and the drilling seal once a year.
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Clear snow quickly after heavy rainfall.
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Plan an annual maintenance : leak check, measurement of refrigeration parameters , cleaning of the battery.
What we guarantee
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Rigorous load calculation for the right power.
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Compliant, clean and durable HVAC installation : stainless steel materials, UV cladding, tidy wiring.
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AirGreen Service throughout Greater Montreal ( Montreal , Laval , Longueuil , North Shore , South Shore ): commissioning, HVAC maintenance and ongoing assistance.
In short
This Sharp ZU1 series (R-32) wall-mounted heat pump installation in Nun's Island combines intelligent elevation , frost management , and silence for immediate and lasting comfort. We apply the same standards to balconies, terraces, and backyard walls, with a finish that meets Montreal's co-ownership and climate requirements.
How it goes, from the first call to the end
The main steps of this kind of job at AirGreen. Every house has its quirks: the estimate brings them out.
We look at the room, the outside wall, the line route and where the outdoor unit will go. That is where the capacity gets chosen.
Model, capacity and price, in writing. We also check whether the model qualifies for assistance programs.
Floors and furniture protected, wall plate position marked level, wall opening located.
A single opening, with the slope the drain needs to flow outside.
Set on a stand raised above the snow, with the clearances the manufacturer requires.
Connected, insulated and protected. The opening is then sealed against water, cold air and insects.
A dedicated circuit and an accessible disconnect near the outdoor unit.
Leak test, vacuum, then start-up and a check of heating and cooling.
Remote, modes, filters: we show you the essentials before we leave.
- The on-site estimateWe look at the room, the outside wall, the line route and where the outdoor unit will go. That is where the capacity gets chosen.
- The quoteModel, capacity and price, in writing. We also check whether the model qualifies for assistance programs.
- Getting readyFloors and furniture protected, wall plate position marked level, wall opening located.
- The wall openingA single opening, with the slope the drain needs to flow outside.
- The outdoor unitSet on a stand raised above the snow, with the clearances the manufacturer requires.
- Lines, cable and drainConnected, insulated and protected. The opening is then sealed against water, cold air and insects.
- The electrical workA dedicated circuit and an accessible disconnect near the outdoor unit.
- Tests and start-upLeak test, vacuum, then start-up and a check of heating and cooling.
- The walkthroughRemote, modes, filters: we show you the essentials before we leave.
What the unit delivers when it is cold
The range as published on airgreen.ca: pick a size to see its capacity in deep cold.
| Size | Heating at −8 °C | Heating at −15 °C | Coldest certified point | COP at −15 °C | SEER | HSPF | Indicative LogisVert aid |
|---|---|---|---|---|---|---|---|
| Sharp ZU1 12 000 | 14,500 | 12,000 | −27 °C: 7,200 | 2.11 | 22.0 | 11.0 | $1,740 |
| Sharp ZU1 15 000 | 18,100 | 15,300 | −27 °C: 10,100 | 2.1 | 24.0 | 11.0 | $2,172 |
| Sharp ZU1 18 000 | 22,000 | 18,000 | −27 °C: 11,500 | 2.2 | 24.0 | 11.0 | $2,640 |
| Sharp ZU1 24 000 | 22,400 | 19,000 | −27 °C: 12,300 | 2.2 | 22.0 | 11.0 | $2,688 |
According to NEEP, it delivers 14,500 BTU/h at −8 °C (17 °F), more than at 8 °C (14,000 BTU/h). It heats as hard in moderate cold as in mild weather.
According to NEEP, its certified maximum capacity at −27 °C (−17 °F) is 7,200 BTU/h, 60% of its nominal 12,000 BTU size.
At 8 °C, its certified maximum capacity reaches 17,100 BTU/h, 42% more than its nominal 12,000 BTU size.
According to NEEP, it delivers 18,100 BTU/h at −8 °C (17 °F), more than at 8 °C (18,000 BTU/h). It heats as hard in moderate cold as in mild weather.
According to NEEP, its certified maximum capacity at −27 °C (−17 °F) is 10,100 BTU/h, 67% of its nominal 15,000 BTU size.
At 8 °C, its certified maximum capacity reaches 21,800 BTU/h, 45% more than its nominal 15,000 BTU size.
According to NEEP, it delivers 22,000 BTU/h at −8 °C (17 °F), more than at 8 °C (21,600 BTU/h). It heats as hard in moderate cold as in mild weather.
According to NEEP, its COP at −27 °C is 1.88: the highest of the ZU1 line, which ranges from 1.79 to 1.82 at that temperature.
According to NEEP, its certified maximum capacity at −27 °C (−17 °F) is 11,500 BTU/h, 64% of its nominal 18,000 BTU size.
At −27 °C, its certified minimum capacity is 3,200 BTU/h (5,500 at 8 °C). It slows down instead of cycling on and off.
According to NEEP, its certified heating capacity at −15 °C (5 °F) is 19,000 BTU/h, 79% of its nominal 24,000 BTU size. Its COP there is 2.20.
Data read live from the airgreen.ca page of each size (NEEP / AHRI certified performance). When the title names the installed size, it is highlighted; otherwise the whole range is shown. The aid shown is today’s, using Hydro-Québec’s rule ($120 per 1,000 BTU/h at −8 °C); amounts quoted in the article date from its publication. Only Hydro-Québec confirms the assistance granted.
And at your place?
Two quick checks with real numbers: what heat costs, and what your current heaters add up to in BTU/h.
Baseboards and electric furnaces turn 1 kWh of electricity into 1 kWh of heat. A heat pump delivers more: that is its COP. At Hydro-Québec’s rate D (11.142¢/kWh above 40 kWh a day, since 1 April 2026):
Hydro-Québec: a heat pump can be up to three times more efficient than baseboards for heating in the colder months.
Estimate per kWh of heat, at the chosen temperature, using the certified COP from the product page. Taxes, access charge and backup heat not included.
Conversion: 1 W = 3.412 BTU/h. An indication, not a load calculation: baseboards and furnaces are often stronger than the real need, and they can stay as backup. AirGreen confirms the capacity on site.
What to do, season by season
Three habits per season for this unit. They take a few minutes and prevent many calls.
- Clean the indoor unit's filters.
- Clear leaves and debris left on the outdoor unit by winter.
- Test cooling before the first hot days.
- Clean the filters more often when the unit runs a lot.
- Keep plants away from the outdoor unit.
- Check that no water drips from the indoor unit.
- Rake the leaves around the outdoor unit.
- Test heating before the first cold days.
- Book periodic maintenance before winter.
- Keep snow away from the stand and the front of the unit.
- Let the unit defrost: it is normal.
- Never hit the ice on the fins; call us if the unit stays iced up.
Which type of equipment for your project?
Pick what looks like your need.
Four mistakes we do not make
Flip each card to see what we do instead.
What people ask us about this kind of work
Does a wall-mounted heat pump heat in winter?
Wall-mounted or multi-zone: how do I choose?
Where does the outdoor unit go?
Are there grants?
Do I need a permit?
How cold can it heat?
How much can I save?
How is the LogisVert assistance calculated?
Is it noisy?
The outdoor unit is covered in ice: is that normal?
Does AirGreen hold the required licences?
Is the estimate free?
No question matches. Write to us: we answer.
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Text and photo: a real AirGreen Climatisation & Chauffage job. The diagrams are generic illustrations of the type of installation, not a survey of this job site. Sources of the added figures: airgreen.ca product pages (NEEP / AHRI performance), Hydro-Québec (Heat pumps page, LogisVert, read on 13 October 2026), Régie de l’énergie (rate D as of 1 April 2026).