It’s a chilly day and you just want to get warm. But it seems like your house just keeps getting colder and colder. That’s the moment your stomach drops – is your furnace broken?
Luckily, there are several common furnace issues you can learn about. Next time you question whether your furnace is working properly, run through this list and see if one of these common furnace problems could be to blame.
Furnace Isn’t Getting Power
The simplest solution is to double-check that it’s plugged in. Accidents happen and it may have accidentally been unplugged. If it is plugged in, the next step is to check the circuit breaker. If it’s in the off position, flip it back on. If the circuit breaker is sitting between on and off, flip it off first and then back on. If it remains on, the trip of the circuit breaker was likely just a coincidence. If not, there might be an issue with your electrical wiring.
Pilot Light Or Ignition Issues
Depending on the age of your furnace, there might be an issue with your pilot light. Check that it’s still lit. If it’s not, go through the process of relighting it. A gust of wind could have blown it out. If it continues to go out, call in an HVAC professional to help you diagnose the cause.
Once your burners have a layer of build-up, they aren’t able to sufficiently release natural gas that creates combustion, meaning you won’t have any heat. If you notice your burner making anything other than a blue flame, this might be the issue. This is extremely dangerous to do yourself unless you know what you’re doing, so call a professional to help you.
Furnace Isn’t Blowing Air
If your furnace does turn on but no air is being blown, chances are your blower fan belt is broken. Consult your owner’s manual for instructions on replacing it.
Thermostat Not Set To Heat
While it might sound silly, double-check that your thermostat is actually on and set to heat. There’s a chance someone in your home turned it off or switched off the heat. Although this is a simple fix, this is one of the most common problems.
Typically a squealing sound indicates a slipped or worn-out blower belt. If you have some mechanical expertise, you might be able to fix this yourself. First, examine the belt because you might just need to tighten it. If wear is obvious, install a new one following the directions in your owner’s manual. You can also call an HVAC specialist to do it for you.
Access Panel Left Open
To get into the inner workings of your furnace, you have to bypass an access panel. If you leave this open, your furnace won’t turn on. Take a minute to double-check the access panel is securely closed.
Faulty Limit Control Switch
Are you noticing the blower fan continuously running, yet you’re positive your thermostat is set to auto, rather than on? It might be an issue with your limit control switch. Found directly below the box that directs heat from the furnace to the ducts, this switch shuts your system down when it hits a certain temperature. This may need to be adjusted or replaced and you should have a professional do it.
Grinding or Scraping Sound
When the furnace’s ball bearings wear out, you’ll start to hear a grinding or scraping sound. As soon as you notice it, turn off your unit and immediately call an HVAC professional to come to make the repairs.
If you don’t regularly replace your furnace filters, the airflow will be restricted, causing your furnace to work hard and that can lead to the heat exchanger overheating. Ultimately this will shut down your unit. In the best-case scenario with a dirty filter, your furnace will simply not work as well. If you can’t remember the last time you changed your filters that might be the issue.
Cracked Heat Exchanger
If the heat exchanger is cracked, your furnace can’t do its job. Even more serious, deadly carbon monoxide could begin to fill your house. Look for:
- Soot on the inside of your
- A strong, unpleasant odor that smells like formaldehyde
- Water on the floor under the furnace
- People in your home complaining of headaches, irritated eyes, nausea, disorientation, or flu-like symptoms (these are indicators of carbon monoxide poisoning)
Popping, Pinging Ducts
When your ducts begin to heat, they expand and as they cool, they will shrink back again. That’s one cause of the popping or pinging sounds. Additionally, the sound of a loose flap of metal wiggling inside the duct might be noticeable. If you’re able to pinpoint the exact location of the sound, you can try making a very small dent and see if the sound stops.