I went down in the basement...I didn't smell anything down there. I thought the source of the smell was coming from the basement near the furnace area. But, I was wrong. I have a burning smell in heat system. Is there any explanation why all of this is happening? Please give me good, accurate, intelligent, non-ignorant answers, please. Thank you so very much! This is a serious matter. Please take this in consideration.
It may be dust in the duct work or on the surface of the heat exchanger, but that usually burns off and the smell goes away after only a couple of cycles. If that is not the case, then you may have a cracked heat exchanger. The gases of combustion pass through the heat exchanger, warming the exchangers metal surfaces on one side. Air being circulated by the blower then picks up the heat from the metal surfaces and is delivered to the duct work. Because of the way the heat exchanger is constructed, the combustion gases and the conditioned air shouldn't mix. The natural byproducts of combustion of natural gas, propane or fuel oil are carbon dioxide and water vapor. Over long periods of time the water vapor will corrode the heat exchanger's metal and eventually eat its way through the metal. If that happens, combustion gases will mix with the circulating air and you get an odd smell. The air being moved by the blower actually interferes with the proper combustion of the fuel and reduces the ability to burn the fuel completely. When you have incomplete combustion, carbon monoxide is formed (a deadly poison). There will also often be aldehyde's present in those gases. They will have a sharp acrid smell and they are irritating to the lungs and nasal passages. You are right, this is a serious matter. You run the risk of carbon monoxide poisoning if there is a cracked heat exchanger. I strongly recommend that you have a qualified hvac service technician come in and check it out. It may save your life or that of a loved one. If the heat exchanger is cracked, it can be replaced. Depending on the age of the unit, you may want to consider replacing it altogether. The service technician will be able to give you the correct information regarding what parts may need to be replaced, how much it should cost and where they can be obtained.
What you smell is dirt, hair, lint etc in your heat ducts. You need to clean them out and/or hire someone to clean the vent system out. It needs done at least once a year. My place had the same problem until I had the vents cleaned. Now it smells just fine.
