Furnace not heating? Here’s what you can do about it:
Your house is cold, your furnace isn’t working, and you don’t want to pay someone to come fix it.
The good news is that some furnace problems can be solved with basic troubleshooting skills. All you need is time and a bit of patience.
Have both of those in spades? Let’s jump in.
First things first, figure out where your furnace is
I know, I know, some of you are rolling your eyes. But, you’d be amazed how often people don’t know where or even what their furnace is. Heck, when I got in this business I thought what heated our home was the hot water heater.
If that’s you right now, here’s what a furnace actually looks like:
Now that we know what a furnace is, let’s figure out where it is.
A good rule of thumb is that if you live in a home built in the last 20-30 years, it’s probably in the attic. If it’s not in the attic (or you have an older home), then it’s most likely in one of the following places: utility closet in your garage, hallway closet, or crawlspace underneath your house.
Found your furnace? Good, let’s move on.
Having trouble finding it and live in Northwest Arkansas? Call us and we’ll walk you through finding it over the phone: 479-282-0003.
Check that your thermostat has power
If you only knew how many calls we run that end in us changing batteries.
I’m serious, before we go any further, check that your thermostat has power. If it’s a battery-powered unit, go ahead and change the batteries, even if it’s not dead. If it’s not a battery-powered unit, check that the circuit breaker for your thermostat hasn’t tripped. If it has, flip the switch and voilà, your thermostat and furnace should be working again.
Thermostat powered on (+ fresh batteries), but furnace still isn’t working?
Let’s keep going.
Check that your furnace has power and is turned on
Despite all the advances in technology, furnaces still need electricity to operate (even gas ones). So if your furnace isn’t getting power, it isn’t running.
The first thing to do is to check your fuse box thoroughly for any off or tripped circuit breakers. If you find one, flip it. There’s a good chance that'll fix your furnace problem.
Note: If your furnace tripped a breaker (the switch was in the "middle" position), it could mean you have electrical problems. Please contact a technician to have your system inspected. If you reset it and it trips again, you absolutely need to have your system inspected because something is seriously wrong.
Fuse box look good, but still no heat?
Check that your furnace is actually powered “on”. To do that, go to your furnace and look for a switch on the outside. It should be easy to find. Make sure it’s switched on, and if not, flip it.
Still no heat? Onward.
Clean your filter
One of the best ways to destroy your expensive heating and cooling system is to not change the filter. As time goes by and debris builds up, your system has to work harder and harder to push air into your home. Eventually, it throws in the towel and quits.
If you’ve been bad about changing your filter, your furnace may have gone into "lock-out" mode to protect itself. Before you reset it though, you need to change your filter. And before you can change it, you have to find it.
Most filters are behind the big metal vent you see in your ceiling (usually a hallway). Here’s what mine looks like:
If you’ve got one of those, carefully open it up and you should see a filter. Make a note of the size of the filter and then go to Walmart (or Amazon) and buy it.
Note: When replacing your filter, be careful to put the filter in the correct way. Most filters have an arrow on them that points in the direction air should flow. That arrow should point up if your filter is behind a metal vent in the ceiling or towards the furnace if next to the actual unit. Sounds backwards, but that’s how your system works.
If you don’t have a filter behind your metal vent, your filter may be located next to the actual furnace unit. To replace it, go to your furnace and look for a door or opening where a filter might hide. Once found, replace it with a clean one.
Replaced your dirty filter with a clean one? Good, let’s move on to the final troubleshooting step.
Reset your furnace
It’s amazing the healing power of yanking an appliance's power cord out of the wall. It’s been fixing internet routers for years and there’s a decent chance it’s going to fix your furnace today.
To reset your furnace, go to your unit and look for the power cord (it should be within five feet or so of the unit). Once you find it, carefully unplug it. After 30 seconds or so, plug it back in.
Note: If you have a really old furnace (pre-1990), you may have to manually re-light the pilot light after resetting.
Is your furnace working? Is hot air coming out of your vents?
I sure hope it is.
The bad news is that if you’ve followed the above steps to the T and your furnace still isn’t working, there’s probably a serious issue with it.
I know, you hoped you would be able to fix it on your own for free.
The good news is that our service calls are just $19, so you can get a friendly, trained Franklin technician out there to diagnose your issue for around the same cost as a couple large pizzas. He’ll figure out what the issue is, recommend a repair, and if you go with it, hopefully have your home warm again within a couple hours.
If you’d like us to come out, just give us a call 24/7 at (479) 282-0003.