Your furnace is an integral part of your home. Without one, you wouldn’t be able to keep warm during cold weather. Yet furnaces can have some issues that are more typical than others.
Let’s review these problems and about what they might cost to correct so you know before you contact an HVAC technician. Some of the most common furnace repair problems include:
- 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 go through all of them.
- Is your thermostat set right? Make sure it’s on “heat,” “auto” and that your preferred temperature is greater than the room’s current temperature. If you have a programmable thermostat, make sure it has new batteries.
- Is the circuit breaker tripped? Your furnace can’t operate 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. Because this switch resembles a light switch, it’s easy to unintentionally turn it off. If it was off, it may take your furnace a few minutes to turn on.
- Is the air filter clean? A dusty air filter can create a lot of issues for your furnace. Replace yours if you can’t see light through it.
Estimated Repair Cost
This issue 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 dropped and tells your furnace to start running.
- The draft inducer fan turns on to bring in fresh air for combustion.
- The gas valve unlocks for the burners, which are ignited electronically.
- The flame sensor signals to your furnace the burners have been lit.
If something is wrong during the sequence, your furnace will shut off as a safety precaution.
A couple of possible causes for this issue include:
- Dirty or malfunctioning flame sensor. If the sensor doesn’t detect a flame, it will turn off your furnace to prevent 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 ultimately need to be replaced.
- 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 fail due to age, damage or dust accumulation.
- Old thermostat. If your thermostat isn’t working correctly, your furnace won’t be able to run.
- Dirty air filter. A dirty air filter can limit airflow and force your furnace to shut down to prevent overheating. Make sure to replace 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 an incorrect thermostat setting or a dirty air filter that’s limiting airflow. Use the steps above to fix the problem.
4. Furnace Won’t Turn Off
If it’s very cold outside or you like your home to be warm, your furnace may be working for a long time.
If this isn’t the case, 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 leaking air, forcing your furnace to run constantly to make up for the air loss.
Estimated Repair Cost
These costs are approximations, so it’s necessary to note yours may be different based on your furnace’s brand and model.
- New blower motor: $250–$800
- Seal ductwork: varies based on square footage
Bon Air Service Company Can Solve Your Furnace Problems Quickly and Affordably
Furnace problems can be a costly headache, but not when you call Bon Air Service Company. We’ve been providing the quality, affordable furnace repair Grand Prairie homeowners have trusted since 2018. Contact us at 972-332-1028 to receive your free estimate today.