Average Repair Costs for 4 Common Furnace Issues

November 30, 2021

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 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 go through all of them.

  • Is your thermostat set right? Make sure it’s on “heat,” “auto” and that your preferred temperature is higher 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 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 accidentally turn it off. If it was off, it might take your furnace a few minutes to start.
  • Is the air filter clean? A dirty air filter can cause a lot of issues for your furnace. Replace yours if you can’t see light through it.

Estimated Repair Cost

This problem 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 starts heating your home.

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

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

A couple of possible causes for this issue include:

  • Dirty or malfunctioning flame sensor. If the sensor doesn’t sense a flame, it will turn off your furnace to prevent natural gas from spilling 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 taken out and changed.
  • Bad limit switch. This safety feature will shut 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 accumulation.
  • Old thermostat. If your thermostat isn’t working properly, your furnace won’t be able to operate.
  • Dirty air filter. A dirty air filter can limit airflow and force 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 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 cases, this problem is linked to an incorrect thermostat setting or a dusty air filter that’s restricting airflow. Follow the steps above to fix the problem.

4. Furnace Won’t Turn Off

If it’s very cold outside or you like your home to be toasty, your furnace may be running for a long time.

If this isn’t the case, ensure 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 sound like your furnace is running all the time.

Alternatively, there might be a problem with the blower motor or your ductwork may be losing air, forcing your furnace to run continuously 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 house size

Garoken Energy Co. Inc. Can Resolve Your Furnace Issues Quickly and Affordably

Furnace issues can be a costly headache, but not when you work with Garoken Energy Co. Inc.. We’ve been delivering the quality, affordable furnace repair Beaverton homeowners have relied on since 1980. Contact us at 503-848-3838 to receive your free estimate today.