Waking up on a chilly day to a freezing house is an annoyance no one wants to deal with. A broken furnace is not just uncomfortable to live with; it can also put your home at risk bursting water pipes, mould, and other issues. You will want to fix this right away.

Gas furnaces today are made more efficiently, which means they are also more complicated than ones built in the past. What might have been a mechanical problem is now a digital issue that involves sensors and computer system testing.

Mangell Plumbing lists down a few simple things you can do to figure out why your furnace stopped working.

Fuse Box

Check this first (especially if this is the first time you started your furnace this year) for any tripped circuit breakers as this could mean a bigger problem with your electrical system. Your heater may also have liftable metal housing that contains a fuse – if it is dark from being burnt it will need replacing. Either way, a technician should be called to ensure there are no other problems with your furnace.

Power Switch

This should go without saying, but sometimes people forget that they turned off their furnace for the summer or, perhaps, it was accidentally turned off. Make sure the power switch is on. The switch is usually mounted on the side of the furnace.


Check that nothing is blocking the air intake and exhaust as not all furnaces breath through chimneys. Sometimes leaves, insects, and moisture can get caught in intakes and exhausts that are attached to the side of the house.


Check its settings to make sure that it’s turned to the heat setting, and the temperature is set high enough for the furnace to turn on. Programmable thermostat settings can be confusing, keep the user guide handy in the event of troubleshooting.

Remember to replace your thermostat batteries when you notice the low battery sign appear. If the display is not turning on at all, it could be because the batteries are already dead and need to be changed.

Air Filters

If your furnace does turn on, but the air is not blowing as hard as it usually does, it might be time to change the air filters. These should be replaced every three months (every season) on most residential heating systems. If air filters get too full of dust, hair, and other particles present in the air, it can restrict airflow.

If after checking all of these parts your furnace still does not work effectively, then it is time to call a licensed technician to inspect your furnace. Expert advice is recommended for newer gas furnaces that are more complex than older models. A service technician can make you aware of issues that are common with your furnace model and how to take care of your model accordingly. They can also diagnose and repair parts before it requires extensive emergency servicing. The best way to make sure your furnace is working well is by getting it checked before the cold weather season starts. Fall maintenance can save you time, money, and disappointment so book an appointment today.