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 problems that are more common than others.
Let’s go over these problems and about what they might cost to correct so you know before you call an HVAC technician. Some of the most common furnace repair issues 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 check all of them.
- Is your thermostat set right? Make sure it’s set to “heat,” “auto” and that your desired temperature is greater 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 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 located on or close to it. Since this switch looks like 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 create a lot of issues 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 follows a specific sequence when it starts heating your home.
- Your thermostat detects the temperature has fallen and tells your furnace to turn on.
- 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 tells your furnace the burners have been lit.
If something is wrong during the sequence, your furnace will shut off as a preventive measure.
A couple of potential causes for this issue include:
- Dirty or malfunctioning flame sensor. If the sensor doesn’t detect 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 taken out and changed.
- Bad limit switch. This safety feature will shut off your furnace if it detects backdrafting. Backdrafting is dangerous, because carbon monoxide and natural gas can leak into your home. These switches can fail due to age, damage or dust buildup.
- Old thermostat. If your thermostat isn’t working properly, your furnace won’t be able to operate.
- Dirty air filter. A dirty air filter can limit airflow and force your furnace to shut down 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 important 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 cases, this problem is linked to an incorrect thermostat setting or a dirty air filter that’s restricting airflow. Follow the steps above to resolve the issue.
4. Furnace Won’t Turn Off
If it’s extremely 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, ensure your thermostat is set correctly and working 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 losing air, making your furnace run constantly to make up for the lost air.
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 house size
Bain Heating & Air Conditioning, Inc Can Solve Your Furnace Issues Quickly and Affordably
Furnace problems can be a costly headache, but not when you call Bain Heating & Air Conditioning, Inc. We’ve been delivering the quality, affordable furnace repair Heflin homeowners have relied on since 1974. Call us at 256-270-1196 to receive your free estimate today.