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Common Furnace Problems That Require Repairs

HVAC technician repairing a furnace

Most homeowners take their furnaces for granted until they find themselves without heat on a cold winter night. An old or poorly maintained furnace is an emergency waiting to happen. Here are some problems you may encounter with your gas or electric furnace that require the attention of an HVAC technician.


Lack of Hot Air

If your furnace is blowing cool air, it won’t heat your home. Often the culprit is a dirty or clogged air filter, easily replaced during routine maintenance. Also, ensure your thermostat is set correctly and the batteries aren’t dead. If your filter is clean and your thermostat functions correctly, it’s time to call an HVAC tech to diagnose the lack of heat.


Overactive Blower

If the furnace fan operates even when it’s warm inside, you’ll need to check the limit switch. This switch turns the furnace on or off according to the unit’s internal temperature. Adjusting and repairing a limit switch is best left to a professional.


Inconsistent Pilot Light

Your gas furnace needs a pilot flame to ignite, and the flame should be blue. If the pilot keeps going out when you light it, the flame setting may be too low. Other causes could be a clogged pilot orifice or a defective safety switch. A yellow or orange flame may indicate an insufficient oxygen supply, which requires cleaning the intake valve.


Failure to Start

If your electric furnace has no power, check to see if the breaker has been tripped or if the power cable is cut or crimped. If you can rule out these possible causes, you may need a pro to diagnose the problem.


Bad Smells

Natural gas smells like rotten eggs. If you notice a sulphuric smell from your furnace, act fast because you may have a natural gas leak. Turn off the gas valve and open windows and doors. Get out of the house immediately and call the gas utility or a trusted HVAC company.


Loud and Unusual Noises

Furnaces are designed to run quietly. If you hear a strange whirring, grinding or clanking noise, you should call a professional to take a look. It may be caused by loose ducts, oil and soot buildup in the chamber or an unbalanced blower fan.


Furnace Maintenance and Repair in Orangeville, Alliston, Erin and Caledon

At Don’s Heating & Cooling, we provide installation, maintenance and repair services for your gas or electric furnace. You can also sign up for a Service Maintenance Plan, so you don’t have to worry about scheduling service calls. Contact us today to book an appointment with a furnace repair technician in Orangeville, Alliston, Caledon and Erin.



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