Your furnace is a key part of your home. Without one, you wouldn’t be able to stay warm during cold weather. Yet furnaces can have some issues that are more common than others.
Let’s review these problems and about what they might cost to fix so you know before you contact 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 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 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 fresh batteries.
- Is the circuit breaker tripped? Your furnace can’t operate 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 located on or close to it. Because 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 turn on.
- Is the air filter clean? A dirty air filter can cause a lot of issues 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 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 unlocks for the burners, which are lit electronically.
- The flame sensor signals to 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 potential 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 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 senses backdrafting. Backdrafting is hazardous, since carbon monoxide and natural gas can seep 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 restrict airflow and force your furnace to shut down 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 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 restricting airflow. Use the steps above to resolve the problem.
4. Furnace Won’t Turn Off
If it’s very chilly outside or you like your home to be toasty, your furnace may be running 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 seem like your furnace is running all the time.
Alternatively, there might be an issue with the blower motor or your ductwork may be leaking air, forcing your furnace to run constantly to make up for the lost air.
Estimated Repair Cost
These costs are estimates, so it’s important 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
Stanford Heating & Cooling Can Resolve Your Furnace Issues Quickly and Affordably
Furnace issues can be a costly headache, but not when you work with Stanford Heating & Cooling. We’ve been providing the quality, affordable furnace repair Bloomfield homeowners have trusted since 1999. Call us at 812-825-8695 to request your free estimate today.