Repair man fixing a HVAC unit.

What Are the Five Most Common Furnace Problems?

Your heater is one of the things you rely on most in your home to keep you comfortable. When something goes wrong with it, you're left in the cold, wondering what is wrong and how you can fix it. Here are some of the most common furnace issues and what might be causing them.

1. No Heat

If your heater isn't producing the one thing it's truly meant to do, it can be frustrating. The first question we ask when we hear about this issue is: Is your thermostat set to heat? We know it's an obvious question, but sometimes the seasons change quickly, and a switch from cooling to heating can be overlooked.

While you're checking, look to see if there is a fan setting on your thermostat. If there is and it's on, your heater is only blowing cool air throughout your home. Another solution to cold air blowing from your heater is that your air filters have become clogged, and it's time to change them!

2. Strange Noises

It's easy to grow accustomed to strange clangs and clicks coming from your heater if they've been present for a while. If you hear knocking or rattling, most likely, something has come loose and needs adjusting. Hear a loud, rumbling sound? That could be leftover fuel in the combustion chamber, in which case, turn off your heater and call a technician immediately.

Keep in mind that all furnaces make some noise, so no need to worry about normal on and off sounds you hear.

3. Pilot Light or Ignition Issues

Old furnaces run using a pilot light that is an ignition source for gas burners. If your pilot light doesn't stay lit, it could be because of several reasons:

  • Clogged pilot orifice

  • Broken thermocouple

  • Low flame setting

  • Defective safety switch

With all of these issues, you should call in an expert as re-lighting the pilot light yourself can be dangerous.

If you have a newer unit with an electric ignitor, check your flame sensor. The flame sensor will shut down the whole furnace if it detects gas but no flames and is a critical safety feature. Yours could be faulty because the sensor has become dirty and can't see the flames. Regular maintenance will keep this problem from recurring.

4. Frequent Cycling

It's normal for your furnace to turn on and off as it tries to keep the set temperature up in your home. But if you notice that it's turning off only after a couple of minutes, and your room still feels chilly, your furnace is short cycling.

This could be caused by a lack of airflow caused by a clogged air filter. Replacing that air filter is your first step in fixing the problem. If you're still experiencing short cycling, the problem could be out of your hands, and you should call an expert.

5. Strange-Colored Pilot Light

If you ever notice that your furnace's pilot light is burning yellow, call in a professional immediately. This is a sign that your system is producing excess carbon monoxide, a colorless and odorless gas that is extremely dangerous for anyone to inhale.

If you want to try to solve simple furnace issues on your own, here are a few safe and straightforward things you can do without training.

  • Check the circuit breaker - it could have tripped, cutting off power to your heater.

  • Look at your thermostat settings - you might not have it set to heat, or the fan could be on.

  • Replace your air filters - this is a very common solution to many problems! We recommend replacing air filters every month to keep your air clean and things running smoothly.

After you've exhausted your own troubleshooting, it is time to call us in to inspect. Furnaces are very touchy, and most repairs require trained hands. We are ready to take on your heater problems. Call us at (856) 512-1832 or contact us online for all your maintenance needs.