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As the Seasons Change, Look for These Signs of Heater Malfunction

Solve These Heater Issues Quick, Before Winter Arrives!

Several red flags can indicate a heater needs repair. Regular repair and maintenance is the best way to prevent a heater from failing. Waking up in a cold house in the middle of winter is certainly not the time to do it! 

Some tell-tale signs of heater malfunction include the following:

  • The air is circulating, but it is not warm enough.
  • The air circulation is inadequate.
  • Energy bills have been unusually high.
  • The heater makes loud noises when in operation.
  • The pilot light is the wrong color (e.g., yellow).
  • The air quality is poor.
  • The heater is 20+ years old.

In this article, experts offer more insight into these heating issues and how they can impact homeowners. 

Blowing Cold Air, Instead of Warm

If the heater has been running for over 10 minutes and has not warmed up, a heater circulating cold air instead of warm is a major red flag. Another possibility may be a failed heat pump. The filter could also be so dirty that it's preventing warm air from circulating properly because the heat exchanger is blocked. This can subsequently cause the exchanger to overheat, which trips a high limit switch. 

There could also be a problem with the pilot light. If the pilot light will not stay lit, or the problem persists with cold air being circulated, call a professional to inspect and repair the heater.  

Strange Noises

scared men

If strange noises are emanating from the heater, they should not be ignored! 

These common heater noises usually mean something is not right, and it's time for repairs: 

  1. Vibrating, rattling sounds can indicate a loose duct.
  2. Rattling can also occur when the heater is not sitting on a steady surface.
  3. Whistling can indicate that a hole or gap has formed in a duct. An air filter that has become completely clogged with dirt can also result in a whistling sound as air struggles to pass through it. 
  4. Squealing noises are indicative of a problem with the belt. 
  5. Humming usually means that there is a problem with the blower motor.
  6. Banging signals that there is probably a duct problem. 

Yellow Pilot Light

The flame of a pilot light should be blue. If it's yellow, that's a problem. Specifically, it means that there is not enough oxygen for proper combustion to take place. Therefore, the flame is weak, and the gas valve will not open due to the lack of heat. A yellow pilot light can also be a sign of danger, as it can produce deadly carbon monoxide. 


A yellow pilot light should be addressed immediately by an HVAC professional, as the situation could potentially be life-threatening. Most heating companies offer 24-hour emergency services for these types of situations. 

About Anderson Heating, Cooling & Plumbing

Anderson Heating, Cooling & Plumbing makes its customers' comfort their top priority since 1982. They offer a wide range of HVAC-related services, including heater repair in Mentor, OH. Call today to speak to a friendly representative and schedule an appointment!

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When you’re dealing with an HVAC or plumbing crisis, it’s nice to see a friendly face. Anderson Heating, Cooling & Plumbing technicians are always friendly, polite, and respectful, so you can have the best possible experience working with us.

Experience You Can Count On

With more than three decades of experience serving the Mentor area, our team is in a unique position to give you the best plumbing, heating, and cooling services possible. We’ve seen it all, so we know just how to handle all your indoor comfort needs.

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At Anderson Heating, Cooling & Plumbing, we are so confident in the work we do that every service is backed by a 100% satisfaction guarantee. If you’re not completely satisfied with our service, we will keep working until you are.

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