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 problems that are more common than others.
Let’s review 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 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 set to “heat,” “auto” and that your preferred 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 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 located on or near it. Because this switch looks like a light switch, it’s easy to unintentionally 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. 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 varies according to 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 fallen and tells your furnace to start running.
- The draft inducer fan turns on to pull in fresh air for combustion.
- The gas valve opens for the burners, which are ignited 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 possible 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 replaced.
- Bad limit switch. This safety feature will turn off your furnace if it senses backdrafting. Backdrafting is dangerous, because carbon monoxide and natural gas can leak 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 cause your furnace to shut off to prevent overheating. Make sure to change 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 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 dusty air filter that’s limiting airflow. Follow the steps above to resolve the problem.
4. Furnace Won’t Turn Off
If it’s extremely 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, make sure 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 on all the time.
Otherwise, there might be a problem with the blower motor or your ductwork may be losing air, making your furnace 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
Mayeuxs AC & Heating Can Solve Your Furnace Issues Quickly and Affordably
Furnace issues can be an expensive headache, but not when you work with Mayeuxs AC & Heating. We’ve been delivering the quality, affordable furnace repair Norco and St. Charles Parish homeowners have trusted since 1984. Contact us at (985) 764-2426 to receive your free estimate today.