Sudden power outage in the heart of the North Shore
At AirGreen , we operate daily throughout Greater Montreal for HVAC (heating, ventilation and air conditioning) system repairs. Recently, our team was called to Sainte-Thérèse , on the North Shore, for an urgent repair of a Carrier central heat pump that had stopped heating efficiently in the early spring.
The client, the owner of a single-family brick home, reported that the central heat pump was producing lukewarm air, despite a properly set thermostat and an apparently operating outdoor unit. The system, a Carrier Performance Series model, fed a network of ducts serving the entire residence.
In-depth diagnosis of the Carrier heat pump
Upon arrival, our certified technicians began a series of comprehensive diagnostic tests to determine the cause of the problem. Here's how our intervention unfolded:
1. Checking electrical parameters
We first checked the power supply voltage to the outdoor unit. The circuit breaker was intact and the voltage was correct, ruling out a power outage.
2. Inspection of compressor and contactor
A slight humming noise was heard at startup: a sign of a worn contactor preventing the compressor from engaging properly. This component, crucial for starting the engine, showed signs of internal carbonization .
3. Refrigeration circuit pressure test
Measurements taken using the digital manifold revealed lower-than-normal pressures. A partial lack of R-410A refrigerant reduced the system's heat transfer capacity, explaining the poor performance.
4. Check the coil and ducts
No major obstructions were detected, but the outdoor coil was clogged with winter dust and debris , limiting heat exchange.
Repair and recommissioning steps
Our experts carried out a complete and methodical repair , ensuring the long-term performance of the Carrier system.
1. Replacing the contactor
The faulty contactor was removed and replaced with a new one, compatible with the Carrier heat pump. This simple component ensures communication between the thermostat and the compressor—an often overlooked, but essential, part.
2. Minor leak detection and repair
Using an electronic leak detector , a micro-leak was located on a connection in the refrigeration circuit. Our technicians re-brazed the affected area and then performed a 300 psi nitrogen test to confirm the system was perfectly sealed.
3. Cleaning the outdoor coil
Using a biodegradable product and low-pressure rinsing, the outdoor condenser was thoroughly cleaned. This cleaning significantly improves efficiency and extends the life of the equipment.
4. Draining the system and recharging
After pulling a full vacuum to remove moisture, we recharged the system with R-410A according to Carrier specifications. Pressures returned to nominal, ensuring optimal operation.
5. Final tests
The final results confirmed the success of the repair:
-
Blowing temperature at 8°C in air conditioning mode;
-
Stable pressures at 120 psi/360 psi;
-
Normal power consumption;
-
Noise level meets standards.
AirGreen Expertise: The Difference of Professional Service
Each AirGreen intervention is based on a rigorous protocol that combines safety, precision and efficiency . In Sainte-Thérèse, our team took care of:
-
Work with calibrated and certified equipment;
-
Comply with environmental standards for handling refrigerant;
-
Check the performance of the complete system, including the interior plenum and thermostat.
Our goal is not just to fix the immediate fault , but to ensure lasting performance for seasons to come.
Maintenance tips for a Carrier central heat pump
Following the intervention, we gave the customer some simple recommendations to extend the life of his heat pump:
-
Change the interior filters every three months.
-
Clean the outdoor coils at the start of each season.
-
Schedule an annual maintenance with a certified technician.
-
Monitor for abnormal noises or excessively frequent compressor cycles.
These good practices prevent the majority of breakdowns linked to fouling, micro-leaks and electrical wear.
Result: restored performance and satisfied customer
Following the repair, the Carrier central heat pump returned to full efficiency. The customer's home now enjoys consistent comfort, both in heating and cooling. The system operates quietly, and final testing confirmed a 25% improvement in energy efficiency .
The client also chose to subscribe to our AirGreen preventive maintenance program , guaranteeing a complete annual check of its HVAC system.
AirGreen: your HVAC partner on the North Shore
Whether in Sainte-Thérèse, Blainville, Laval or Montreal , we offer a complete repair, installation and maintenance service for HVAC systems for all brands — Carrier, Lennox, Trane, Goodman, Midea, Fujitsu, Sharp, Zephyr and many others.
Our mission: to offer a professional, fast and sustainable service, combining technology, know-how and transparency.
Each client benefits from an accurate diagnosis , honest solutions and personalized follow-up .
Technical sheet of the intervention
-
Device type: Carrier central heat pump
-
Location: Sainte-Thérèse (North Shore)
-
Problem: Faulty contactor and minor refrigerant leak
-
Solution: Contactor replacement, solder repair, cleaning, R-410A recharge
-
Result: Restored performance and optimized energy efficiency
AirGreen — HVAC expertise serving the comfort of Quebec homes.