Your furnace is an integral 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 issues 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 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 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 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 found on or near 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 start.
- Is the air filter clean? A dusty 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 problem can be complex, so the estimated cost to repair it varies according to what’s wrong.
2. Furnace Won’t Stay Lit
Your furnace follows a certain sequence when it starts heating your home.
- Your thermostat detects 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 opens 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 down as a preventive measure.
A couple of potential causes for this problem 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 over time. While cleaning during annual furnace maintenance can help, yours may ultimately need to be taken out and changed.
- Bad limit switch. This safety feature will turn off your furnace if it detects backdrafting. Backdrafting is dangerous, 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 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 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 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 tied to a wrong thermostat setting or a dusty air filter that’s limiting 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 running for a long time.
If this isn’t the case, ensure 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 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 important 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
TopTec Heating, Cooling, Plumbing & Electrical Can Solve Your Furnace Problems Quickly and Affordably
Furnace problems can be an expensive headache, but not when you work with TopTec Heating, Cooling, Plumbing & Electrical. We’ve been delivering the quality, affordable furnace repair Libertyville homeowners have trusted since 1993. Call us at 847-362-0262 to receive your free estimate today.