Furnace Repair


Troubleshooting your furnace.
Here are a few issues furnace owners frequently encounter and the usual reasons for why they're happening.
Common furnace issues and their causes
Low heat/no heat
- Thermostat malfunction
- Malfunctioning pilot light
- Underpowered unit
- Gas line issue
- Thermostat malfunction
- Malfunctioning pilot light
- Underpowered unit
- Gas line issue
Frequent on/off cycling
- Thermostat malfunction
- Malfunctioning pilot light
- Underpowered unit
- Gas line issue
- Refrigerant leaks
- Faulty compressor
- Limit switch failure
Blower running more frequently than usual or continuously
- Thermostat malfunction
- Malfunctioning pilot light
- Underpowered unit
- Gas line issue
- Refrigerant leaks
- Faulty compressor
- Limit switch failure
Rumbling, rattling, or squeaking
- Thermostat malfunction
- Malfunctioning pilot light
- Underpowered unit
- Gas line issue
- Mechanical issues
- Airflow reduction
- Clogged burner
- Other mechanical issues
Inconsistent temperature
- Thermostat malfunction
- Malfunctioning pilot light
- Underpowered unit
- Gas line issue
- Refrigerant leaks
- Faulty compressor
- Dirty or clogged air filters
Pilot light going out
- Thermostat malfunction
- Malfunctioning pilot light
- Underpowered unit
- Gas line issue
- Excessive drafts
- Thermocouple malfunction
- Faulty ignition or pilot
- Airflow issues
Repairs and Servicing
Ready for winter? In Canada, it's important to make sure your home is ready for the extreme wind, snow, ice and sub-zero temperatures our winters can bring. Staying comfortable during the cold months starts with having the right heating system that runs smoothly and efficiently all season long.

A thermostat doesn’t simply take your input about how to manage the heat in your home, it’s also the brains of your HVAC system and plays a critical role in making sure it operates properly. What could seem like an issue with your actual furnace unit could actually be your thermostat.
By the way, all customers who buy or rent a furnace through Sterling receive a free smart thermostat.
We fix a wide range of mechanical malfunctions, including but not limited to:
- Slipped or frayed blower motor belt
- Flickering or yellow flame on the pilot light
- High limit switch - furnace is overheating
- Worn out ball bearings - you’ll hear that squeaking
We regularly encounter systems with poor airflow in need of serious attention to ensure proper airflow in the ducting system.
- Dirty air filter - can cause a gradual loss of air flow from the furnace
- An air filter that properly fits your furnace filter rack
- Annual furnace maintenance
- This can lead to increased electricity consumption
If your furnace venting is not sloped properly, it can lead to leaks and other problems. One common issue we see is primary seal failure, which can be repaired with a small replacement. Another issue is an overflowing condensate pump, which requires disassembly, cleaning, and potentially replacement of the drain lines.
Gas line issues can cause not only catastrophic problems, but also more common and simple ones. Some signs of gas leaks include a rotten egg smell, physical symptoms like fatigue or dizziness, dead or dying vegetation in your home, and groggy pets who are closest to the floor and therefore most affected by gas leaks. It is important to address gas line issues promptly to avoid further problems.
Our technicians are equipped to repair a variety of electrical issues with furnaces and heating systems, including faulty starting capacitors, dirty fuses, thermostat control wires, and loose wires.
Many customers skip maintenance and simply wait for something to go wrong.
- Regular maintenance is the best way to ensure repairs, particularly ones that affect comfort and safety, are anticipated and dealt with immediately.
- High-efficiency furnaces have more safety sensors in the cabinet now and need to be maintained with regular maintenance.
- The manufacturer of your unit may require annual maintenance for your warranty to remain in force.
Learn more about the types of furnace maintenance and inspections we offer or explore our SterlingCare protection plans.
We carry, install, and service all major makes and models.








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