Your furnace is a key 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 issues and discuss what they might cost to correct so you know before you call 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. The 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 correctly? Make sure it’s set to “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 near it. Since this switch resembles 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 dusty air filter can cause a lot of issues for your furnace. Get a new one if you can’t see light through it.

Estimated Repair Cost

This problem can be complicated, so the estimated cost to repair it varies according to what’s wrong.

2. My Furnace Won’t Stay Lit

Your furnace follows a specific sequence when it begins heating your home.

  1. Your thermostat detects the temperature has dropped and tells your furnace to start running.
  2. The draft inducer fan turns on to bring in fresh air for combustion.
  3. The gas valve unlocks for the burners, which are ignited electronically.
  4. The flame sensor tells 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 potential causes for this issue include:

  • Dirty or malfunctioning flame sensor. If the sensor doesn’t sense a flame, it will shut off your furnace to prevent natural gas from spilling 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 taken out and changed.
  • Bad limit switch. This safety feature will turn off your furnace if it detects backdrafting. Backdrafting is hazardous, because 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 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 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. My Furnace Won’t Blow Hot Air

In many cases, this problem is linked to a wrong thermostat setting or a dusty air filter that’s limiting airflow. Follow the steps above to fix the issue.

4. My Furnace Isn’t Shutting Off

If it’s very chilly outside or you like your home to be toasty, 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 seem like your furnace is on all the time.

Alternatively, 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 air loss.

Estimated Repair Cost

These costs are estimates, 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

Comfort Zone, LLC Can Solve Your Furnace Issues as Soon as Possible

Furnace issues can be a costly headache, but not when you work with Comfort Zone, LLC. We’ve been delivering the quality, affordable furnace repair Cape Coral homeowners have relied on since {year}. Call us at 239-214-0411 to receive your free estimate today.