Your furnace is an integral part of your home. Without one, you wouldn’t be able to stay warm during cold weather. Yet furnaces can have some problems that are more typical than others.

Let’s review these issues and discuss what they might cost to fix 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. My Furnace Can’t Start

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 desired temperature is greater than the room’s current temperature. If you use a programmable thermostat, make sure it has new 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. Since this switch resembles a light switch, it’s easy to unintentionally turn it off. If it was off, it might take your furnace a few minutes to start.
  • Is the air filter clean? A dusty air filter can cause a lot of problems for your furnace. Replace yours 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 Isn’t Staying Lit

Your furnace uses a certain sequence when it begins heating your home.

  1. Your thermostat notices the temperature has fallen 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 lit.

If something is off during the sequence, your furnace will shut off as a preventive measure.

A couple of potential causes for this issue include:

  • Dirty or malfunctioning flame sensor. If the sensor doesn’t detect a flame, it will turn off your furnace to keep 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 replaced.
  • Bad limit switch. This safety feature will shut off your furnace if it senses backdrafting. Backdrafting is dangerous, because 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 limit airflow and force your furnace to shut down 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 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. The Furnace Won’t Blow Hot Air

In many instances, this problem is tied to an incorrect thermostat setting or a dirty air filter that’s restricting airflow. Follow the steps above to resolve the issue.

4. The Furnace Isn’t Shutting 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 what’s happening, make sure 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 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 be different based on your furnace’s brand and model.

  • New blower motor: $250–$800
  • Seal ductwork: varies based on square footage

J.L. Brady Company LLC Will Work Hard to Solve Your Furnace Issues as Soon as Possible

Furnace problems can be a costly headache, but not when you work with J.L. Brady Company LLC. We’ve been providing the quality, affordable furnace repair Moline homeowners have relied on since {year}. Call us at 309-517-7511 to request your free estimate today.