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furnace troubleshooting

A Comprehensive Furnace Troubleshooting Guide

If you happen to live in an area with frequent cold weather, you probably have a furnace. Furnaces are great because they work all the time with little effort required to maintain them, but sometimes you’ll need to rely on your furnace troubleshooting knowledge to fix an issue.

Having a furnace break-down at least a handful of times in your home is rather common and easy to deal with if you know what to do when it happens.

But before you jump the gun and call in a professional team to fix your furnace for a price, here are a few tips you can use to troubleshoot the problem and potentially get the issue resolved without spending any of your hard-earned money. Here’s what you can do when your gas furnace is not working.


Check Your Furnace Filter


Your furnace most likely has a filter, which filters out dust and debris from the air before it circulates it around your home. As you can imagine, this filter can become clogged over time.

Before you check on your furnace, turn off your thermostat and turn off the furnace switch as well. When checking your filter, remove it and hold it up to the light. If light can barely make it through your filter, you need to replace your HVAC filter. You should check the filter once a month, and remember to make sure the arrows are pointing towards the airflow when you install a new one. Don’t forget to place the access panel tightly back in place when you’re done.


Check Your Thermostat


If your filter is clean and your furnace is still acting up, the next place you’ll want to check is the thermostat. Make sure that it’s set to “heat” and try adjusting it upward by about 5 degrees more than the room temperature.

You might need to replace the batteries if they’ve run out. If you have an electromechanical thermostat you can open it and dust off the inside as well. In addition, make sure your thermostat isn’t getting false readings from stuff like ovens, lamps, heaters, or sunlight.


Check Your Electrical Panel and Furnace Switch


The problem might not lay with the filter or the thermostat, but the power in your home instead. See if your furnace switch has been accidentally flipped off and if so, flip it back on if it has.

If that doesn’t do the trick, go to your electrical panel and see if your power is on at the fuse box or breaker box. Make sure your HVAC breaker is turned on and look for any switch that’s not facing the same direction as the others. That’s the one you’ll want to flip.

If it’s your fuse box that’s the problem, you’ll probably have to replace a dysfunctional fuse with a new one of an identical type. Once you’ve done all this, turn your furnace back on and see if it’s working. If the power still doesn’t come on, it’s time to call a professional.


Check Your Furnace Flame


If your furnace flame is healthy, it will be blue, with a small yellow tip. This color means that a gas furnace is burning its fuel efficiently and safely. If the flame is ANY other color than blue, turn your furnace off and call a professional right away. There could be a serious problem and it could mean that your gas wall furnace needs repair.


Relight the Pilot


If your pilot light has gone out, you’ll need to relight it. You can do this on your own easily. Turn the gas to your furnace off for about 15 minutes and if you still smell gas after this amount of time, stop what you’re doing immediately, you have a gas leak. Evacuate your family and call in the pros.


Secure the Access Panel


Another reason why furnaces may stop working may be because the front access panel isn’t completely in place. Check to make sure it’s secured all the way.


Check Your Vents


Sometimes the cause of a dysfunctional furnace isn’t the furnace itself, but the vents connected to it. Make sure your vents aren’t blocked before calling in the professionals.


Clearing any Furnace Troubleshooting Issues


In conclusion, there any are many reasons why your furnace might not be working properly, but if you know your furnace troubleshooting basics you can often fix the problem without spending money.

Remember to go through every step on this checklist before you call in a professional team, and you’ll be able to take care of the problem yourself a large majority of the time.

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