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 go over these problems and discuss what they might cost to fix so you know before you contact an HVAC technician. Some of the most common furnace repair issues involve:
- Furnace won’t turn on
- Furnace doesn’t stay lit
- Furnace won’t blow hot air
- Furnace won’t turn off
1. My Furnace Will Not 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 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 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 turn on.
- Is the air filter clean? A dirty air filter can cause 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. The Furnace Won’t Stay Lit
Your furnace uses a specific 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 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 off during the sequence, your furnace will shut down as a preventive measure.
A couple of possible 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 getting 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 turn off your furnace if it detects backdrafting. Backdrafting is dangerous, since carbon monoxide and natural gas can leak into your home. These switches can fail due to age, damage or dust accumulation.
- Old thermostat. If your thermostat isn’t working correctly, your furnace won’t be able to operate.
- Dirty air filter. A dirty air filter can restrict airflow and cause your furnace to shut down 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. The Furnace Is Blowing Cold Air
In many instances, this problem is linked to an incorrect thermostat setting or a dusty air filter that’s restricting airflow. Use the steps above to fix the issue.
4. My Furnace Can’t Shut Down
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 going 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 constantly to make up for the air loss.
Estimated Repair Cost
These costs are approximations, 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
B & B Heating & Cooling Will Work Hard to Resolve Your Furnace Issues as Soon as Possible
Furnace issues can be an expensive headache, but not when you work with B & B Heating & Cooling. We’ve been delivering the quality, affordable furnace repair Florissant and St. Charles homeowners have trusted since year. Contact us at 314-325-7552 to request your free estimate today.