Temperatures will drop this winter, and when they do, you need a functioning heater to keep you and your family warm and comfortable. Furnaces are built to be durable, but even trustworthy, leading-brand heating systems sometimes malfunction.
If your heater blows cold air, hot air, or no air at all, try these troubleshooting tips before you call a professional.
Before you investigate your furnace, check your thermostat. The following questions may be helpful as you troubleshoot:
- Is your thermostat set to “cool” instead of “heat”? (We’re not being facetious-this happens to the best of us.)
- Does your thermostat run on batteries? Check to make sure the batteries aren’t weak or dead.
- Is the furnace on? Raise the temperature on your thermostat by about five degrees and listen for the furnace to rumble to life.
- Is your thermostat an older model? Carefully open your thermostat and blow lightly to shake dust and debris from the wires. Make sure it hasn’t been dislodged from the wall and that all wires securely connect together.
- Have your thermostat’s wires become disconnected from the furnace? Trace the wires back to the furnace and repair any broken wires with electrical tape.
- Are your programmed settings working? Sometimes thermostats default to the technician settings and disregard your programmed preferences. You can override this by manually choosing the temperature you want and pressing the hold button (or consult your user’s manual. Can’t find it? Don’t worry-most thermostat companies now have their user’s manuals online).
If you’ve done all you can with your thermostat and still don’t see results, turn to your furnace.
First, check your breakers and shutoff switches. Locate the wall switch near your furnace and make sure it is on.
Check the circuit breaker and turn it on if needed; also make sure that the furnace’s fuse hasn’t blown. If it has, you’ll need to contact a professional to replace it.
Your furnace has a blower motor, but if the front panel somehow dislodges, the motor won’t turn on. Make sure the front panel door is secure and the switch underneath it is completely depressed-otherwise, the furnace won’t work.
There’s also a possibility that your furnace’s motor is overloaded and needs to be reset. You’ll find the reset button somewhere near the motor. If you press the button and nothing happens, wait about 30 minutes and try one more time.
If your furnace troubleshooting doesn’t seem to help, take a look at the furnace’s filters.
Your Furnace’s Filters
Most furnace malfunctions originate because of a dirty filter. It’s easy for filters to become clogged with dirt and dust, especially because people don’t clean their filters regularly.
When your filter becomes dirty, the airflow becomes restricted, and the heat exchanger in your furnace overheats quickly and shuts off. If you can hear the furnace running but don’t feel any hot air coming out, replace or clean the filter.
Even if your furnace isn’t malfunctioning, make sure to clean your filter once a month. Remember: if you have kids, pets, or other dust-producers, replace your filter even more frequently. A dirty filter causes soot to build up on and around the heat exchanger. Additionally, this buildup reduces your furnace’s efficiency and shortens its lifespan.
Consult your user’s manual to find out where the filter is and how to remove it. Before you clean your filter, remember to turn the furnace and thermostat off to prevent burns. To clean it, hold the filter up to a light-if you can’t see through it, it is too dirty to work effectively.
Check these other possible problems before you consult with your heating specialist:
- Is the gas on? Sometimes someone can turn off the gas valve and forget to turn it back on. Check your meter and make sure that your gas is on (the handle of your gas valve should be parallel to the gas pipe). Older furnaces have pilot lights, so check to make sure that is still lit.
- Is your chimney flue clogged? Sometimes birds or small animals build nests in this area. Turn off your thermostat and furnace, and then carefully dismantle the duct and clean out any debris you find. Then, carefully reassemble the flue and turn the thermostat and furnace back on.
- Are your drain lines dirty? Your furnace drains several gallons of water on a cold day, and the sediment in the water can clog your drain lines. Mold can also restrict water flow. You can flush the drain lines with a solution of water and bleach (3 parts water, 1 part bleach). Not sure how to flush the lines? Ask an expert to do it for you.
Be careful as you inspect the aspects of your heating system. When in doubt, always call your HVAC specialist. Don’t wait around in the cold talk to your heating expert today.