Estimated Repair Costs for 4 Common Furnace Problems

November 30, 2021
Man repairing something

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 problems and about 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. Furnace Won’t Turn On

There are a couple of 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 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 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 found on or close to 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 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 complicated, 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.

  1. Your thermostat notices the temperature has dropped and tells your furnace to start running.
  2. The draft inducer fan turns on to pull in fresh air for combustion.
  3. The gas valve unlocks the burners, which are ignited electronically.
  4. The flame sensor signals to your furnace that the burners have been ignited.

If something is wrong during the sequence, your furnace will shut down as a safety precaution.

A couple of possible 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 keep natural gas from getting 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 turn off your furnace if it senses back-drafting. 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 limit airflow and cause your furnace to shut off to avoid 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 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 an incorrect thermostat setting or a dirty air filter that’s restricting airflow. Follow the steps above to fix the problem.

4. Furnace Won’t Turn Off

If it’s extremely 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 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 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

Winters Heating and Cooling Can Solve Your Furnace Issues Quickly and Affordably

Furnace problems can be a costly headache, but not when you work with Winters Heating and Cooling. We’ve been providing the quality, affordable furnace repair Franklin & South Indy homeowners have trusted since 2019. Call us at 317-406-5382 to request your free estimate today.