5 Quick Furnace Fixes Anyone Can Do Before Calling a Repairman

Service man talking with a woman

October 18, 2013

With Northern California’s cold weather in full swing, you rely on your furnace more than ever. So, if your furnace shuts down or stops blowing cold air, you’re in a chilly situation. However, fixing the problem can be easier than you think.

These 5 fixes can solve most furnace problems without you needing to pay for a repairman to come out.

1. Change the furnace’s air filter if it’s dirty

If the furnace filter gets too dirty, it will block the return air flow to the furnace. It’s like putting a blanket on your head and asking you to breathe normally.

A dirty filter causes these problems:

  • Reduces volume of hot air blown out– Blocked return air means the furnace has less to blow out your supply vents, leaving you chilly.
  • Furnace shuts down– Because your furnace has to run longer to heat your home, the heat exchanger overheats, causing the furnace to automatically shut down.

A dirty filter will also cause soot to build up in the heat exchanger, causing your furnace to run inefficiently and reduce it’s life span. Check the air filter every one to three months and change it if it’s dirty.

REMEMBER: Turn off your furnace’s shut off switch (found on the furnace) and set the thermostat to off before changing the air filter.

2. Check your thermostat

There may be nothing wrong your furnace at all. Your thermostat, the control centre of your heating system, may be the culprit.

If your furnace isn’t coming on or isn’t blowing hot air try these simple troubleshooting tips with your thermostat before you call a repairman:

  • Set the thermostat to “heat” instead of “cool.” (You never know who have been messing around with it and changed it to cool.)
  • Set your thermostat to 5 degrees above room temperature to see if your furnace comes on.
  • Replace the batteries.
  • Open your thermostat’s panel and gently blow out any dust or debris.

3. Make sure the blower motor panel is shut

If someone opened the blower’s panel to do a repair, they may not have shut the panel properly If it’s not pressed in all the way, a safety device will prevent the furnace from running. So, make sure you securely shut furnace blower panel.

4. Inspect your air ducts

Let’s say your furnace seems to be working fine. Blower is running, hot air is coming out…in most rooms. You’ve got a few cold spots in your home. Why? The answer is in your air ducts.

First, check for handles protruding from the ducts. These are dampers that control the airflow. Make sure they’re fully open (i.e., the handle is parallel with the ductwork).

If some of your rooms are still cold, your ducts may have gaps, cracks or holes in them allowing the hot air to escape. This is what we call leaking ducts. These leaks not only make the room cold, but it

Find where the leaks are in the ducts and seal them with a mastic sealant.

5. Make sure the gas valve is open

Like with the blower panel, someone may have shut the gas valve to do a repair and forgot to turn it back on on. If it’s off, no gas will enter the furnace, so nothing will burn. Simply turn it back on (the handle should be parallel with the gas pipe) and you’re good to go.

When in doubt, call a professional

Obviously, these fixes won’t solve all your furnace problems. So, if none of these do the job, it’s best to call a professional for help.

If your furnace has a problem and you live in the East Bay, San Jose, and Sacramento area. contact Service Champions for help.

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