In a condo in Ville-Marie , we were called in to perform a complete cleaning of a Gree wall-mounted heat pump (mini-split indoor unit). Even though the unit seemed to be working “correctly” on a daily basis, the client described a decrease in comfort, a less strong airflow and, above all, a feeling of less fresh air — a typical scenario when fine dust and moisture accumulate in invisible areas (coil, turbine, condensation tray, drain).
At AirGreen , we approach residential HVAC cleaning as an operation focused on performance and air quality: we don't just "rinse the filters." We restore the system to a clean, stable, and safe condition, protecting the home and verifying its operation after the service (displayed temperature, airflow, condensate drainage, operating modes).
Context: a wall-mounted unit installed high up in a modern living space
The Gree indoor unit is installed high up, above an opening, which is common in Montreal condos: the goal is to maximize air distribution efficiency and minimize clutter. This type of installation requires a clean and controlled work method, because even the slightest splash can damage a wall, ceiling, or finishes.
We therefore began with a rigorous setup: protection of surfaces, control of drainage and installation of a washing cover adapted to the unit.
System type: Gree wall-mounted heat pump (mini-split)
This is a Gree wall-mounted heat pump , a compact indoor unit with a supply air flap and setpoint display (here, a display of 23 is observed during testing). This format is very common in Greater Montreal because it combines:
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efficient heating in mid-season and often in winter (depending on the series),
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air conditioning in the summer,
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piece-by-piece inspection
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energy consumption generally lower than an old auxiliary electric system.
Model (consistent, without overinterpretation)
The exact model is not visible in the photo. Visually, the unit corresponds to a recent generation Gree wall-mounted heat pump , type Livo (consistent size and design for residential use). In any case, the cleaning method and critical points remain the same for a Gree wall-mounted unit of this category.
What we actually clean (and why it's crucial)
A “quick” cleaning (filters only) sometimes slightly improves airflow, but does not address the underlying causes: biofilm, greasy dust, bacteria/micro-molds and deposits that settle where air passes and water condenses.
Here are the key areas we address during a complete cleaning :
1) Filters : the first barrier, but not the only one
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Filter removal
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Controlled cleaning and rinsing
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Condition check (deformation, ingrained soiling)
Clean filters protect the rest of the system… but are not enough if the heat exchanger and turbine are already loaded.
2) Coil (evaporator) : the thermal core
The coil is a heat exchange surface. When it is clogged:
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the machine force,
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yield is falling
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the air may take on a musty smell,
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The condensation clings instead of draining properly.
We use a cleaning approach adapted to wall units: safe product, controlled rinsing, complete recovery of wastewater (not on the walls, not on the floor).
3) Turbine/ventilation wheel : a frequent source of odors
This is a major issue. The turbine accumulates dust and deposits, then redistributes them with each cycle. The result: less powerful airflow, sometimes more noise, and odors that return even after simply cleaning the filters.
We carry out a thorough cleaning of the blower area and the turbine, with the following objective: to restore a stable airflow, free of residual contaminants.
4) Condensation tray : where moisture stagnates
Condensation is normal in air conditioning mode (and sometimes in dehumidification mode). But if the tank is dirty:
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biofilm + odors
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risk of overflow
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unstable drainage
We clean the tank and check the drainage points.
5) Drainage and evacuation : preventing damage and breakdowns
A partially blocked drain can cause:
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leaks,
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safety stops,
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persistent humidity around the unit.
We confirm the flow and the absence of blockage, with a clean restart.
AirGreen Method: clean, safe, condo-friendly
In a finished residential environment (white walls, clean ceilings, passageways), our priority is twofold: technical result + site cleanliness .
Specifically, our intervention includes:
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protection of surfaces around the unit (wall, ceiling, floor)
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installation of a wash cover to direct the water towards a container
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Controlled cleaning (no random "spray")
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Wiping and restoring a flawless visual appearance
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Functional check at the end (temperature, modes, blowing, drainage)
Expected results after a thorough cleaning
After this type of cleaning, the most frequent benefits are:
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Fresher, less stale air (especially in enclosed rooms)
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a significant reduction in musty odors
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more constant airflow
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improved temperature stability (the machine reaches the setpoint more easily)
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reduction of the risk of leaks and erratic drainage
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improved daily energy efficiency (fewer "forced" cycles)
In Ville-Marie, in condos where the kitchen, living room and hallway often share the same air volume, a clean appliance makes a real difference to overall comfort.
How often should a Gree wall-mounted heat pump be cleaned in Montreal?
Without being dramatic, here is a realistic benchmark for Greater Montreal:
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Filters : every 4 to 8 weeks during periods of intensive use (heating/air conditioning)
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Complete cleaning : generally once a year , sometimes twice if:
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pets at home,
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works/renovations,
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Frequent cooking without an effective hood
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allergies/asthma
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recurring odors or weaker breathing.
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Conclusion: Simple maintenance that protects your comfort
This intervention in Ville-Marie perfectly illustrates why a complete cleaning of a Gree wall-mounted heat pump is one of the best “return on investment” in HVAC maintenance: you improve air quality, you stabilize performance, and you reduce the risks of condensation problems — all while maintaining a discreet and efficient unit, perfectly suited to the urban Montreal lifestyle.
At AirGreen , we do this work cleanly, methodically, and with particular attention to the interior finishes of the condos.