A common complaint, odors can usually be segregated into 5 classifications. They are:

• Electrical odor

• Burning odor

• Gas odor

• Oil odor

• Damp and musty odor

Electrical odors: Are usually caused by parts overheating. Blower motors are a typical example. Bearings seize up; the motor overheats and insulation on the wires and windings start to melt, causing the odor. Loose electrical connections can also cause wires to overheat with the same results.

Unlikely as it seems; dirty filters can also cause the odor. If the air flow is restricted sufficiently, it can cause electric resistance heaters to overheat. even burn out.

Burning odors:  Similar to electrical odors only worse, especially when accompanied by smoke. Parts, wiring and even debris around the furnace can all   contribute to this odor.

Gas odors:  This is he one that causes the most fear. People automatically think of gas explosions or carbon monoxide. Well, gas explosions are rare and carbon monoxide, for the most part, is odorless.

However, gas odors should not be taken lightly. Try to pin point the source. Most common is a pipe leak or from the furnace itself. If you can't locate the leak, yet feel that the odor persists, call the Gas Company and if very strong, open the windows.

Oil odors:  Usually easy to find (and easy to correct) as it stems from a leak/drip or an improperly operating oil burner.

A leak is easy to spot; just look for the oil at the tank, the burner or the oil lines, and tighten or replace the defective part. If there is no visible sign, then it probably is a burner problem.

This can be caused by too many things to list here. from blocked chimney to a plugged burner. Your best bet here is to call for service.

Damp and musty odor:  This is more common in the air conditioning mode. Attics, damp basements and/or crawl spaces, water damaged ductwork and/or equipment, combined with air leaks in ductwork are the most common source of damp, musty odors. But this odor problem is almost never due to a problem with your equipment.

Summary:  Remember to check for clean air filters. Check to see if the fan is working, for air leaks in damp places, for oil stains or unusual noises or strong gas odors. These all indicate problems and should not be ignored.

Hope this has been of some assistance, however they are just rough guidelines and not all possible conditions are covered. Hope this has been of some assistance, however they are just rough guidelines and not all possible conditions are covered.

Remember:  The company You Choose To Install and Service Your System Will Determine The Degree of Comfort and Satisfaction You Enjoy.

Excerpts of the preceding information has been compiled by Hannabery HVAC, which has graciously permitted us to include them on this web site as a service for all homeowners.

These "Common HVAC Problems" are provided FREE and as a consequence Climatemakers does not assume any liability resulting from any information we provide.  In all cases where there is any possibility of injury, consequential damage, direct damage to your equipment or when recommended by the equipment manufacturer, your system should be repaired , inspected or maintained by a qualified technician.

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