It’s cold out and your furnace has stopped working. But before you call a professional, you want to make sure it’s not something easy you could fix yourself, right?

Then you’re in the right place. Here are a few things you can check before calling a furnace repair company.

1. Make sure your thermostat is on

This sounds silly, but it happens. (It’s easy to accidentally bump your thermostat.) Go to your thermostat and check that the thermostat is:

  • On and functioning (if not, you may need to replace the battery)
  • Set to “heat”
  • Set to “auto”
  • Set at least 3 degrees above room temperature

2. Change your air filter

A dirty air filter can restrict the airflow to your furnace, causing it to overheat and shut off. If your furnace seems to turn on for a short time and then shut off before heating up your home, your air filter could be the culprit.

Check the filter and change it if it looks dirty.

3. Check your circuit breaker

If there’s no air coming out of your vents at all, then your furnace might not be getting power at all. Go to your main electrical panel and look for a circuit labeled “furnace” or “heater”.

Try flipping it all the way off and then back on again. If you have a fuse-type panel, make sure the fuse is still good.

Note: If your furnace continues to flip your circuit breaker or blow fuses, stop using it and get a professional electrician to take a look. There’s likely a larger problem and you could be making it worse by running it.

4. Look for a power switch near your furnace

Some furnaces are plugged into an outlet that has a switch to turn off the power. This switch looks a lot like a regular light switch so it can sometimes be inadvertently flipped (while putting away a few Christmas decorations, perhaps?)

Look for the switch near your furnace and try flipping it on to see if that solves your problem.

5. Check the Pilot Light

Those with a gas furnace must always check the pilot light if the furnace has no power. If the gas supply to the furnace stops, the pilot light will go out, and the furnace will stop working.

To turn the pilot light back on, follow these steps:

  1. Turn off the furnace and wait a couple of minutes for it to power down completely
    • Never adjust anything on or in your furnace while it is running, as this could cause further damage
  2. Read the manufacturer’s instructions for specific steps on how to relight the pilot light
    • Most furnaces have a label on it with these directions, but if you can’t find the label, check the manual or search for the information on the manufacturer’s website
  3. Find the gas valve, usually located near the furnace’s bottom
    • There should be three indicators (pilot, on, off)
    • Turn the knob or switch to the “pilot” position
  4. Hold the reset button, which is usually red
    • Those with a manual pilot light will need an external flame source, like a long match, to relight the pilot light
  5. Turn the gas and furnace back on and observe for other issues
    • If the pilot light burns steadily, you can put the switch or knob back in the “on” position

If your furnace’s problems continue, contact an HVAC expert. Also, if you notice discoloration when you check the pilot light, get professional help.

6. Inspect Air Ducts

If there are cold spots in your home, even though hot air is coming out of the air vents, the issue could be different from your furnace not working. Instead, it could be the air ducts.

Locate the handles (dampers) that protrude from the ducts. These control airflow. Open all the dampers fully.

If an entire room is cold, the air ducts may be leaking or have a faulty design. Both of these issues will significantly increase your energy bill, so you must act quickly to identify the problem.

To find blocks or leaks, inspect the ducts you can access. Check that no furniture, drapes, plants, or other objects aren’t blocking the vents.

If you notice gaps between ducts or sections that branch out, you can seal them with special metal duct tape. However, it’s best to let an HVAC expert do this for you. It is their job, after all, to clean and repair air ducts, so their expertise will ensure the problem doesn’t persist. They can also inspect hard-to-reach sections of the air ducts.

7. Check the Blower Motor

Lastly, if your furnace is not getting power, check the blower motor. When the furnace activates, you’ll hear the blower motor start. When it turns on, you should feel warm air coming out of the vents.

However, if you hear the furnace ignite but don’t hear the blower motor turn on or warm air doesn’t come out from the vents, it could be because the blower motor failed. In this situation, you’ll need the help of a professional.


Call for Help When Your Furnace Has No Power

Still need help? It’s time for a professional furnace repair company. Ragsdale has been serving the Atlanta metro area since 1996 and provides expert heating repair, service and installation.

Schedule an estimate now for your repair.

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