11 Things to Inspect When Your Furnace Acts Up

11 Things to Inspect When Your Furnace Acts Up

. 4 min read

The furnace is a reliable heating unit within the home. But sometimes, it can deceive you by stopping work for a while.

There are a few facts you might like to inspect before you make a call to the professional. When your furnace stops working, the things you must check are discussed below:

1. Thermostat Issues

Start with the thermostat to troubleshoot a furnace. Open the thermostat. Gently blow any debris or dust that might have clogged it. You should take a look to see if the machine is heating well enough to activate the unit. Be sure to set the thermostat's temperature higher than the room temperature.

2. Thermostat’s Batteries

If the thermostat doesn't seem to work correctly, you may need to change your thermostat’s batteries. Some thermostats can be electrical, while others may use batteries. If the thermostat is battery-operated, the cells might have been dead.

You might want to buy them as there are many affordable furnace repairs. You should switch them at least once a year or while it's needed. It will show a low-battery symbol when they are in need of changing.

3. The Switch

If your thermostat is okay, check if the unit’s power is switched on. If maintenance work or repairs were recently executed on your furnace, be sure to check out if it was turned back on or not.

The switch is usually planted beside the unit or anchored on the wall. Don't forget to check if your furnace has a switch with a fuse. Be sure to check if it’s begrimed and scorched. Replace it if necessary and turn the switch back on.

4. The Breaker

If your furnace is still not working while the switch is on, check to see if there is a tripped breaker. You should test the breaker by flipping it from pillar to post. Get surety that it is staying in the ON status.

This can be supportive in resetting the breaker. You could have a problem with the wiring in the circuit if it doesn't work. Or, the circuit breaker itself is a problem. If that's the case it'll be best to have a licensed electrician or a professional inspect it.

5. The Furnace Filter

Air filters often get dirty and clogged, which might result in inefficient performance of the furnace. It becomes the culprit by trapping dust, hair, and other particles, which causes restrictions or blocks the vital airflow over time.

It might overheat the heat exchanger and forestall your furnace from working well. You can purchase a new filter to fix the issue. It should be switched every three or four months or as the recommendation is given in the manual.

6. The Air Duct

You may have a problem with leaking ducts or incorrectly designed ducts if your home has cold spots, even when the air vents are producing enough hot air. It increases your energy bill. Check thoroughly if there is any blocked or leaky duct. You can use metal duct tape to seal it so that you can have a controlled airflow.

7. Vents and Register

Your vents and registers might be closed or clogged if the furnace is functioning, but the house remains cold. Make sure your vents are open. Check if any tapestries or appliances are obstructing them. Cleaning regularly will help you to escape these problems.

8. Panel Door

Make sure to keep your front panel door secure. Safety switches can be on the front panels, which won’t allow the furnace to engage if it’s not closed decently in some modern furnaces. Read and check the manual if you are hesitant.

9. Pilot Light

There is a pilot ignition with gas furnaces. You likely have a faulty or dirty igniter if it does not fire up even after your furnace clicks on or initiates the start cycle. Maintain the instructions in the manual and relight the pilot. If it doesn't stay on after a few shots, then you might need a repair job from a professional.

10. Flame Sensor

Check the flame sensor to see if it's dirty or not. The flame sensor can malfunction if it's not cleaned properly. Oxidation or carbon build-up might restrain the flame sensor's capability to work accordingly. So, you should consider cleaning it from time to time. Clean the skewer on the flame sensor. Scrape it with some glass paper. Be mindful and wary of not breaking anything.

11. Gas Supply

You should check to make sure that the gas faucet to the furnace is accessible. A turmoil of the gas supply to the heating device might take place. Deluge could leave your heating structure without fuel. If you can smell propane, you definitely require a professional’s help.


The furnace is necessary equipment to have when the cold is extreme. It keeps us warm and lets us enjoy the winter. Its seasonal maintenance is essential. Sometimes it may stop working for a tiny reason.

If you make sure to check out the things above, you might not have to rush for the electricians or repairmen every now and then. But first, be sure to have the skills when undertaking any work on the furnace. To prevent a minor issue from becoming a major problem, inspect your system at least as frequently as the manufacturer's recommendation.

Wish you enjoy a warm and comfy winter time!



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Mark Thompson

Mark is an Australian Agronomist and a father of two beautiful girls. He enjoys writing about garden design, landscape architecture, DIY, tools, and related topics.

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