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 go over these issues and about what they might cost to correct so you know before you call 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 couple of 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 set to “heat,” “auto” and that your desired temperature is higher 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 close to it. Because this switch resembles a light switch, it’s easy to unintentionally turn it off. If it was off, it might take your furnace a few minutes to start.
- Is the air filter clean? A dirty air filter can create a lot of problems for your furnace. Get a new one if you can’t see light through it.
Estimated Repair Cost
This issue can be complicated, so the estimated cost to repair it depends on what’s wrong.
2. Furnace Won’t Stay Lit
Your furnace uses a specific sequence when it starts heating your home.
- Your thermostat notices the temperature has dropped and tells your furnace to turn on.
- The draft inducer fan activates to bring in fresh air for combustion.
- The gas valve opens for the burners, which are lit 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 preventive measure.
A couple of potential causes for this issue 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 spilling into your home. The ignition process corrodes flame sensors over time. While cleaning during annual furnace maintenance can help, yours may eventually need to be replaced.
- Bad limit switch. This safety feature will shut off your furnace if it senses backdrafting. Backdrafting is hazardous, since carbon monoxide and natural gas can seep into your home. These switches can fail due to age, damage or dust buildup.
- 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 restrict airflow and cause your furnace to shut off to prevent overheating. Make sure to change 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 an incorrect thermostat setting or a dirty air filter that’s restricting airflow. Follow the steps above to fix the issue.
4. Furnace Won’t Turn Off
If it’s very chilly outside or you like your home to be warm, your furnace may be working for a long time.
If this isn’t the case, make sure your thermostat is set correctly and running 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 on all the time.
Otherwise, there might be a problem with the blower motor or your ductwork may be leaking air, forcing your furnace to run continuously to make up for the lost air.
Estimated Repair Cost
These costs are approximations, 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 square footage
Honke Heating & AC Can Resolve Your Furnace Issues Quickly and Affordably
Furnace problems can be a costly headache, but not when you call Honke Heating & AC. We’ve been providing the quality, affordable furnace repair Gresham homeowners have trusted since 1969. Contact us at 503-663-8033 to receive your free estimate today.