Your furnace is an integral part of your home. Without one, you wouldn’t be able to stay warm during cold weather. Yet furnaces can have some problems that are more common than others.
Let’s go over these issues and about what they might cost to fix so you know before you contact an HVAC technician. Some of the most common furnace repair issues involve:
- Furnace won’t turn on
- Furnace doesn’t stay lit
- Furnace won’t blow hot air
- Furnace won’t turn off
1. Furnace Won’t Turn On
There are a few reasons why your furnace won’t turn on, so make sure to check all of them.
- Is your thermostat set correctly? Make sure it’s on “heat,” “auto” and that your preferred temperature is higher than the room’s current temperature. If you use a programmable thermostat, make sure it has fresh batteries.
- Is the circuit breaker tripped? Your furnace can’t run if it doesn’t have power. Reset the switch if it’s facing the outside of the electrical panel.
- Is the furnace switch off? Your furnace has a power switch found on or close to it. Since this switch looks like a light switch, it’s easy to unintentionally turn it off. If it was off, it might take your furnace a few minutes to turn on.
- Is the air filter clean? A dirty air filter can cause a lot of problems for your furnace. Replace yours if you can’t see light through it.
Estimated Repair Cost
This problem can be complex, so the estimated cost to repair it depends on what’s wrong.
2. Furnace Won’t Stay Lit
Your furnace follows a certain sequence when it starts heating your home.
- Your thermostat notices the temperature has fallen and tells your furnace to start running.
- The draft inducer fan turns on to bring in fresh air for combustion.
- The gas valve opens for the burners, which are ignited electronically.
- The flame sensor tells your furnace the burners have been ignited.
If something is wrong during the sequence, your furnace will shut down as a preventive measure.
A couple of possible causes for this problem include:
- Dirty or malfunctioning flame sensor. If the sensor doesn’t sense a flame, it will shut off your furnace to keep natural gas from getting into your home. The ignition process corrodes flame sensors as time passes. While cleaning during annual furnace maintenance can help, yours may eventually need to be taken out and changed.
- Bad limit switch. This safety feature will turn off your furnace if it senses back-drafting. Backdrafting is dangerous because carbon monoxide and natural gas can leak into your home. These switches can malfunction due to age, damage, or dust buildup.
- Old thermostat. If your thermostat isn’t working correctly, your furnace won’t be able to operate.
- Dirty air filter. A dirty air filter can reduce airflow and force your furnace to shut off to avoid overheating. Make sure to replace yours every 30 to 90 days, or anytime you can’t see light through it.
Estimated Repair Cost
These costs are estimates, so it’s necessary to note yours may fluctuate based on your furnace’s brand and model.
- Flame sensor: $350–$500
- Limit switch: $150–$300
- Thermostat: $150–$350
- Furnace filter: $10-$30
3. Furnace Won’t Blow Hot Air
In many instances, this problem is linked to a wrong thermostat setting or a dusty air filter that’s restricting airflow. Follow the steps above to resolve the problem.
4. Furnace Won’t Turn Off
If it’s extremely cold outside or you like your home to be warm, your furnace may be working for a long time.
If this isn’t what’s happening, ensure your thermostat is set correctly and working properly. If your fan setting is at “on,” the blower motor will be running even when the furnace isn’t, so it’ll sound like your furnace is running all the time.
Alternatively, there might be a problem with the blower motor or your ductwork may be losing air, forcing your furnace to run continuously to make up for the air loss.
Estimated Repair Cost
These costs are estimates, so it’s important to note yours may be different based on your furnace’s brand and model.
- New blower motor: $250–$800
- Seal ductwork: varies based on house size
Kowalski Heating, Cooling & Plumbing Can Resolve Your Furnace Problems Quickly and Affordably
Furnace problems can be a costly headache, but not when you work with Kowalski Heating, Cooling & Plumbing. We’ve been providing the quality, affordable furnace repair McMurray homeowners have relied on since the 1980s.