Your furnace is a key 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 issues and discuss 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. 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 preferred 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 found on or near it. Because this switch looks like 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 dirty air filter can create 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. My Furnace Isn’t Staying Lit

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

  1. Your thermostat detects the temperature has dropped and tells your furnace to turn on.
  2. The draft inducer fan activates to bring 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 shut off your furnace to keep 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 eventually need to be taken out and changed.
  • Bad limit switch. This safety feature will shut off your furnace if it detects backdrafting. Backdrafting is dangerous, since carbon monoxide and natural gas can leak into your home. These switches can malfunction due to age, damage or dust buildup.
  • Old thermostat. If your thermostat isn’t working correctly, your furnace won’t be able to operate.
  • Dirty air filter. A dirty air filter can reduce airflow and force your furnace to shut down to avoid overheating. Make sure to replace 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. The Furnace Blows Cold 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 issue.

4. The Furnace Won’t Turn Off

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

If this isn’t what’s happening, make sure your thermostat is set correctly and working 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 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 lost air.

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 square footage

JBR Mechanical Can Solve Your Furnace Issues as Soon as Possible

Furnace issues can be a costly headache, but not when you call JBR Mechanical. We’ve been delivering the quality, affordable furnace repair Bedford homeowners have relied on since year. Call us at 812-266-9785 to request your free estimate today.