
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 problems that are more common than others.
Let’s review these problems and discuss what they might cost to correct so you know before you call an HVAC technician. Some of the most common furnace repair issues 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 correctly? Make sure it’s on “heat,” “auto” and that your desired temperature is higher than the room’s current temperature. If you have a programmable thermostat, make sure it has new batteries.
- Is the circuit breaker tripped? Your furnace can’t operate 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 located on or near it. Because 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 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 complicated, so the estimated cost to repair it varies according to what’s wrong.
2. Furnace Won’t Stay Lit
Your furnace uses a specific sequence when it begins heating your home.
- Your thermostat notices the temperature has fallen and tells your furnace to start running.
- The draft inducer fan turns on to bring in fresh air for combustion.
- The gas valve opens for the burners, which are ignited electronically.
- The flame sensor tells your furnace the burners have been ignited.
If something is wrong during the sequence, your furnace will shut down as a preventive measure.
A couple of potential 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 prevent 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 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, 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 correctly, your furnace won’t be able to run.
- Dirty air filter. A dirty air filter can restrict airflow and force your furnace to shut down to avoid 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 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 cases, this problem is linked to a wrong thermostat setting or a dusty air filter that’s limiting airflow. Use the steps above to fix the problem.
4. Furnace Won’t Turn Off
If it’s very chilly 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 working properly. If your fan setting is at “on,” the blower motor will be going even when the furnace isn’t, so it’ll seem 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, making your furnace run continuously to make up for the lost air.
Estimated Repair Cost
These costs are estimates, 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
Central Heating & Plumbing Can Resolve Your Furnace Problems Quickly and Affordably
Furnace problems can be a costly headache, but not when you work with Central Heating & Plumbing. We’ve been delivering the quality, affordable furnace repair New Castle homeowners have relied on since {year}. Contact us at 724-401-1843 to receive your free estimate today.