Your furnace is a key part of your home. Without one, you wouldn’t be able to keep warm during the winter. Yet furnaces can have some issues that are more typical than others.
Let’s go over these problems and about what they might cost to fix so you know before you call an HVAC technician. Some of the most common furnace repair problems 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 right? Make sure it’s set to “heat,” “auto” and that your desired 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 electricity. 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 near it. Since this switch resembles a light switch, it’s easy to accidentally turn it off. If it was off, it may take your furnace a few minutes to start.
- Is the air filter clean? A dirty air filter can cause a lot of issues for your furnace. Get a new one if you can’t see light through it.
Estimated Repair Cost
This problem can be complicated, so the estimated cost to repair it depends on what’s wrong.
2. Furnace Won’t Stay Lit
Your furnace follows a specific sequence when it begins heating your home.
- Your thermostat detects the temperature has dropped and tells your furnace to start running.
- The draft inducer fan activates to pull in fresh air for combustion.
- The gas valve opens for the burners, which are ignited electronically.
- The flame sensor signals to your furnace the burners have been ignited.
If something is off during the sequence, your furnace will shut down as a safety precaution.
A couple of possible causes for this problem include:
- Dirty or malfunctioning flame sensor. If the sensor doesn’t sense a flame, it will turn 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 shut off your furnace if it detects backdrafting. Backdrafting is hazardous, because carbon monoxide and natural gas can leak into your home. These switches can malfunction due to age, damage or dust accumulation.
- Old thermostat. If your thermostat isn’t working properly, your furnace won’t be able to run.
- Dirty air filter. A dirty air filter can limit airflow and force your furnace to shut off to avoid overheating. Make sure to change yours every 30 to 90 days, or whenever you can’t see light through it.
Estimated Repair Cost
These costs are estimates, so it’s necessary to note yours may vary 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 limiting airflow. Follow the steps above to fix the problem.
4. Furnace Won’t Turn Off
If it’s extremely chilly outside or you like your home to be warm, your furnace may be running for a long time.
If this isn’t what's happening, ensure your thermostat is set correctly and running properly. If your fan setting is at “on,” the blower motor will be going even when the furnace isn’t, so it’ll seem like your furnace is running all the time.
Otherwise, there might be an issue with the blower motor or your ductwork may be leaking air, forcing your furnace to run continuously to make up for the air loss.
Estimated Repair Cost
These costs are estimates, so it’s necessary to note yours may vary based on your furnace’s brand and model.
- New blower motor: $250–$800
- Seal ductwork: varies based on house size
Select Comfort Systems Heating & Air Conditioning Can Solve Your Furnace Issues Quickly and Affordably
Furnace problems can be an expensive headache, but not when you call Select Comfort Systems Heating & Air Conditioning. We’ve been providing the quality, affordable furnace repair West Valley City homeowners have trusted since 1996. Contact us at 801-305-4777 to receive your free estimate today.