An urgent call for poor performance
At AirGreen , we know that a clogged wall-mounted air conditioner can quickly turn a comfortable summer into a nightmare. This is exactly what happened to a customer living in Sainte-Julie , on the South Shore of Montreal , who contacted us regarding inefficient cooling and poor indoor air quality .
Upon arriving on site, our technician immediately noticed a classic sign: the front of the indoor unit was displaying a significant accumulation of dust, and a slight damp odor was emitted as soon as the system was turned on. The model in question—a Midea 12,000 BTU wall-mounted air conditioner running on R-32 refrigerant —was approximately four years old and had never received a full service since its installation.
Complete diagnosis and alarming findings
Upon opening the front cover, our team quickly identified the cause of the problem: the air filters were completely saturated with dust and fine particles . As can be seen in the photo, the filter grilles, a turquoise blue typical of Midea units, were covered with a layer of compact dirt, limiting the passage of air to less than 20% of its normal capacity.
Direct consequences observed:
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Loss of energy efficiency : the compressor ran continuously without ever reaching the required temperature.
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Ice buildup on the evaporator: Reduced airflow was causing thermal imbalance.
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Increased electricity consumption , because the device had to compensate for the lack of circulation.
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Degraded air quality , with an increased presence of dust and spores.
This scenario is typical of poorly maintained HVAC systems. Although Midea units are known for their reliability, they require filter cleaning every 3 to 6 months , depending on the home environment.
AirGreen intervention: deep cleaning and refurbishment
Our comprehensive repair and maintenance protocol followed four key steps:
1. Disassembly and internal inspection
We carefully removed the filters, front fairing, and directional louver. A visual inspection of the evaporator coil revealed a thin film of mold and a slight oily deposit, the result of a mixture of dust and moisture.
2. Ecological high-pressure cleaning
The evaporator, condensate tray and filters were cleaned with dry steam using a biodegradable HVAC-certified product, which is safe for health and surfaces. This process eliminates 99.9% of bacteria and restores heat exchange performance.
3. Checking the condensates
We then unblocked the partially blocked condensate drain to prevent any risk of internal water leakage. This often-overlooked problem can cause wall damage and fungal growth if left untreated.
4. Performance test and final calibration
After reassembly, a comprehensive test confirmed a blowing temperature of 8°C , fully in line with Midea specifications. The airflow returned to its initial power, and the compressor was able to operate at a reduced cycle, thus optimizing power consumption.
Final result: restored comfort, purified air
A few minutes after the intervention was completed, the client immediately felt the difference: a constant and silent flow of cold air , a fresh smell , and a stable temperature throughout the room.
We also took the time to explain to him how to:
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Clean the filters yourself with clean water once a month during the summer period;
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Schedule annual preventative maintenance with our AirGreen team before each hot season;
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Regularly check that the condensate drain is free to flow .
AirGreen Recommendations: Maintenance = Performance
A well-maintained Midea wall-mounted air conditioner can last over 12 years while maintaining optimal energy efficiency. We recommend all residents of Montreal, Laval, Longueuil, the North Shore, and the South Shore to inspect their filters before the start of each summer.
A clogged filter like the one in Sainte-Julie not only reduces cooling performance, but can also:
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Increase the electricity bill;
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Damage the fan motor;
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Promote the proliferation of mold;
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Lead to premature compressor failure.
At AirGreen, our goal is not just to repair, but to prevent . By scheduling regular maintenance for your HVAC system , you ensure comfort, air quality, and peace of mind all season long.
Another satisfied customer on the South Shore
This service in Sainte-Julie perfectly illustrates the added value of our interventions. It wasn't a major breakdown, but rather a case of neglected maintenance that could have been costly in the long run. Thanks to our rapid response, the customer regained a healthy environment and a high-performance appliance—ready to face the coming summer heat.
AirGreen – HVAC Experts in Montreal, Laval, Longueuil, North Shore and South Shore
Always ready to respond to emergencies and extend the life of your heating and air conditioning systems.