Installation of a Sharp ZU1 wall-mounted heat pump in Le Sud-Ouest
Loft du Sud-Ouest : Sharp ZU1 wall-mounted heat pump installed in the upper part, gravity drain, discreet capping and rigorous commissioning. AirGreen, the careful HVAC installation in Greater Montreal.
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.
A loft-style interior design: performance, discretion and optimized airflow under a concrete slab
In a loft -style condo in the Le Sud-Ouest sector, the objective is clear: replace an inefficient portable system with a compact wall-mounted heat pump , capable of ensuring 4-season comfort while respecting the clean aesthetic of the home (exposed concrete ceiling, open volumes, decorative arches). The priorities set with the client: clean visual integration, minimal noise level, homogeneous airflow in the living area and simplified maintenance.
We are choosing a Sharp ZU1 (capacity 12,000 to 18,000 BTU depending on load calculation), modulating inverter , appreciated for its thermal stability, its easy-access filters and its reliability in an urban Montreal environment.
Why the Sharp ZU1 in a Montreal condo?
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Continuous modulation : the inverter compressor adjusts precisely to demand, reducing on/off cycles and power consumption.
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Mid-season comfort : the heat pump takes over from baseboards, limiting electricity peaks and improving air quality thanks to constant circulation.
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Silence : the interior operation is discreet, ideal for an open plan living room-kitchen-office.
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Filtration and maintenance : washable pre-filters, front access, easy maintenance reminder to integrate into an annual HVAC maintenance plan .
Load study and sizing
Before installation, we carry out a thermal assessment taking into account:
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of the open surface of the living room and the mezzanine,
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concrete ceiling (high thermal inertia),
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southwest-facing windows,
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the infiltration rate and internal contributions (equipment, occupants).
The calculation leads to a range of 12,000 to 18,000 BTUs . In a loft, a slight controlled oversizing may be justified to catch up with summer heat peaks, but we avoid excessive units that cause short cycles , unnecessary noise and insufficient dehumidification. The chosen solution maintains an excellent SEER/HSPF in real use.
Interior layout: high corner under slab, above an arch
The indoor unit is fixed at the top , at the top of a wall return forming an arch . This placement offers several advantages:
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Air diffusion along the axis of the open area, without direct blowing onto the occupants.
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Effective recovery under concrete ceiling, promoting the mixing of hot air masses which accumulate there.
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Aesthetics : the white hull blends into the partition, the lines remain simple.
Our points of attention:
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Clearances around the device for maintenance and proper breathing of the exchangers.
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Fixings adapted to the support (metal anchors in light frame reinforcements; checking the concrete wall if necessary).
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Acoustic treatment : installation on pads to prevent any vibration transmission to the partition.
Refrigeration and finishing
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Optimized line length (approximately 3 to 6 m depending on the configuration), limiting bends and pressure losses.
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Brazing under nitrogen , deep vacuum , pressure resistance and systematic leak testing .
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Continuous closed-cell insulation on liquid and suction, UV protection on the outside.
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Discreet light-colored capping , aligned with the edges of the partition for a neat finish.
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Wall penetration with sleeve and vapor barrier to prevent air bridges and whistling.
Condensate management
In this condo, the gravity slope is preferred: the drain serves a discreet discharge point with siphon and odor check valve . When the architecture requires it (beams, horizontal lengths), we integrate a silent condensate micro-pump into an access box. Here, the topology allowed a short and reliable route, limiting maintenance and moving parts.
Power supply and compliance
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Dedicated circuit from the panel, gauge adjusted to the nominal intensity and maximum current of the ZU1.
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Disconnect switch installed externally near the condenser for safe intervention.
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Protected routing : sealed conduits and fittings, drip loop, clear identification of conductors.
Commissioning: AirGreen protocol
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Cleaning and inerting of lines during brazing.
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Pressure test (nitrogen) then high vacuum with stability to the micronmeter.
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Controlled start-up in cold then hot; verification of overheating and subcooling according to the manufacturer's curves.
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Setting speeds, orientation of shutters, activation of silent modes and basic programming.
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Knowledge transfer : filters, washing, HVAC maintenance interval, effective instructions (23–24°C summer; 20–21°C mid-season).
Results obtained
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Rapid reduction of temperature in the living area, better uniformity up to the corners of the mezzanine.
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Humidity controlled in summer thanks to continuous modulating operation.
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Very low noise : low perception even during heat peaks.
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Aesthetics : minimalist integration without any visible parasitic sheathing.
Grants and Eligibility
Wall-mounted heat pumps that meet the low-temperature performance criteria and required certifications may be eligible for current programs. For each project in Montreal , Laval , Longueuil , on the North Shore and the South Shore , we validate:
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the correspondence of the model of the ZU1 range selected with the required thresholds,
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the production of supporting documents (approval numbers, installation photos, detailed invoicing).
Loft Operating Tips
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Airflow : orient the shutters to sweep the volume and break the stratification under the concrete ceiling.
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Stable setpoint : avoid rapid variations which force starts.
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Interior doors : Keep them ajar to extend the heat pump 's effect to adjacent areas.
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Sun management : blinds/curtains in the afternoon to limit solar gain on south-west windows.
Maintenance and durability
An annual maintenance is recommended:
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control of intensities and temperatures,
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drain check (slope, cleanliness),
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inspection of refrigeration and electrical connections,
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dusting/washing of filters and exchangers.
At AirGreen, our HVAC maintenance plans ensure sustainable seasonal performance, extend equipment life, and maintain the manufacturer's warranty.
Common pitfalls to avoid (feedback from the field)
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Oversized loft units : unstable comfort and insufficient dehumidification.
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“Flat” drain : source of overflows and odors — always plan for the slope and the trap.
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Undersized fixings in the partition: vibration risk; use suitable anchors and reinforcements.
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Shutters not properly oriented : a draft feeling. A precise initial adjustment changes everything.
Deadlines and organization
For a condo in the Southwest :
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Technical visit : 45–60 minutes (measurements, routing, electrical validation).
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Installation : 1 typical day (drilling, refrigeration lines, drain, testing, finishing).
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Discount : demonstration, advice, grant documents, photo file.
Why AirGreen in Greater Montreal
Our teams operate weekly in Montreal , Laval , Longueuil , the North Shore and the South Shore . Our approach: an HVAC installation designed for the reality of local buildings (concrete slabs, tight vertical circulation, condominiums), clean finishes and transparent monitoring. The result: a wall-mounted heat pump that is visually invisible but is felt through stable comfort and controlled operating costs.
Conclusion
The Sharp ZU1 installed in Le Sud-Ouest ticks all the boxes for a Montreal loft: minimalist aesthetics, homogeneous airflow in a large space, quiet operation, and simple maintenance. Accompanied by our commissioning protocol and best operating practices, the equipment offers reliable and economical 4-season comfort . For a similar project, AirGreen guides you from sizing to finishing , then ensures maintenance to protect performance over time.
Areas served : Montreal , Laval , Longueuil , North Shore , South Shore .
Services : HVAC installation , replacement, optimization, HVAC maintenance .
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?
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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).