What to Do if Your Furnace Stops Working

Woman wearing a parka, shivering in front of a broken thermostat - indicating a broken furnace

A broken furnace is a problem every homeowner wants to avoid, especially during the colder winter months. If your furnace stops working, don’t worry, these safe and simple steps can help to resolve it.

Check the Thermostat Settings

Start with the basics of furnace maintenance with some thermostat troubleshooting.

Set Thermostat to “Heat” Mode

First, check the thermostat mode and make sure it’s set to “Heat” mode and not “Cool” or “Eco”. Those other settings can provide cost savings, but may mean the furnace is not noticeably running.

Adjust Temperature to a Higher Setting

Next, conduct a thermostat settings check. A minor thermostat temperature adjustment might be required to activate the furnace again.

Verify the Power Supply

The furnace power supply might also be at fault. You can check the furnace fuse and furnace breaker to see if this is true. However, don’t undertake any electrical work without a professional.

Check Circuit Breaker or Fuse Box

Inspect the furnace circuit breaker or fuse box. If either has tripped, reset the furnace breaker and test the furnace again.

Confirm Power Switch Near Furnace

Next, locate the furnace power switch, which is usually on the side of the appliance. Check furnace power is on: the switch should be set to “on” and not “off”.

Inspect the Furnace Filter

A dirty furnace filter can also cause a furnace to shut down. Conduct a furnace filter check by removing the filter to inspect for dust and dirt buildup. Replacing a clogged filter is essential. A clean filter is critical for correct airflow and performance.

Check the Pilot Light or Ignition System (Gas Furnaces)

If you have an older system, conduct gas furnace troubleshooting by completing a pilot light check and furnace ignition system check.

Ensure the Pilot Light is Lit

If the pilot light is out, follow the manufacturer’s instructions to relight the pilot light safely. This is usually located at the bottom of the furnace.

Examine Ignition for Electronic Systems

For newer electronic ignition furnaces, check for any flashing error codes or malfunctions in the ignition system. Consult the manual for furnace ignition troubleshooting, or call Pro West if you need a professional.

Inspect the Air Vents and Registers

Blocked furnace vents can restrict airflow and reduce the heating efficiency of your appliance. Check the air vents and make sure they are open and unobstructed. Move any obstructions like furniture or rugs that may affect furnace performance.

Look for Any Error Codes on the Furnace

The furnace’s control board or thermostat might display furnace error codes. Furnace LED codes are typically blinking or flashing lights. Take note of the furnace troubleshooting codes and consult the manual to make sense of them.

When to Call a Professional for Furnace Repairs

If basic troubleshooting hasn’t solved the issue, it’s time to call a furnace repair provider and book a professional furnace service.

Persistent Issues After Troubleshooting

Ongoing furnace issues could be a sign of serious problems. If your furnace won’t start after basic checks, call a technician at Pro West to come and take a look.

Strange Noises or Odors

Contact a professional immediately if there are strange noises (banging, grinding, rattling etc.) or a furnace burning smell as these are signs of serious mechanical issues.

Gas Leaks or Safety Concerns

Evacuate your home and contact a professional immediately if there are any signs of a gas furnace leak.

Frequently Asked Questions About Furnace Troubleshooting

Why Won’t My Furnace Turn On?

Common reasons your furnace won’t start include clogged filters, incorrect thermostat settings, and power supply issues.

What Should I Do if My Furnace Smells Strange?

If there is a strange furnace odor, turn off the appliance immediately and call a professional. Don’t take chances with furnace smells.

How Often Should I Replace My Furnace Filter?

You should install a furnace filter replacement every three months. Consult the manual for optimal filter change frequency.

Still Need Help Getting Your Furnace Working?

Call us at 604-990-7550 to get started if your furnace stops working! Furnace repair tips can resolve basic issues, but if problems persist, don’t hesitate to contact Pro West Heating & Air Conditioning for professional assistance in the greater Coquitlam and Lower Mainland regions. We can get your furnace back up and running again.