Estimated Repair Costs for 4 Typical Furnace Problems

November 30, 2021

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 issues that are more common than others.

Let’s review these issues and about what they might cost to fix so you know before you contact 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 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 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 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 close to it. Because this switch resembles 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 dusty air filter can create a lot of issues for your furnace. Replace yours if you can’t see light through it.

Estimated Repair Cost

This issue can be complex, so the estimated cost to repair it depends on what’s wrong.

2. Furnace Won’t Stay Lit

Your furnace uses a certain sequence when it begins 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 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 possible 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 prevent 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 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 correctly, your furnace won’t be able to run.
  • Dirty air filter. A dirty air filter can reduce airflow and force your furnace to shut down to avoid overheating. Make sure to change 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 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. Furnace Won’t Blow Hot Air

In many instances, this problem is tied to an incorrect thermostat setting or a dusty air filter that’s restricting airflow. Use the steps above to resolve 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, 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 losing air, making your furnace 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

J & J Air Conditioning Can Resolve Your Furnace Problems Quickly and Affordably

Furnace problems can be a costly headache, but not when you call J & J Air Conditioning. We’ve been providing the quality, affordable furnace repair Eastland homeowners have relied on since 1981. Contact us at 254-355-3833 to request your free estimate today.