THINGS TO CHECK IF BAD ODORS COME FROM SYSTEM WHEN RUNNING:
- Fungal Infection
within the heater, cooling coil and ducts is the most common problem when smells come from the heated air. See the details of this fungal invader from one of the other pages of this site and use your back button to return here if you desire. Fungi, algae and molds are becoming more common inside the new high efficiency systems and many of the older models as well. Some will produce unpleasant odors when heated and others will produce odors just as bad even in the cooling mode. The page mentioned above will inform you of the details of this terrible problem with more information than you may want to know.
- Burned wires
can be anywhere and may be the very problem. Check for these carefully and repair any that you find. As a wire flows high current it naturally produces heat, but if a connection is poor and loose, it will heat up tremendously. The outer coating will melt and the process of destruction of the wire and its coating will move backward toward the source gradually, but sometimes rather rapidly, depending on the load and the heat produced.
These can be dangerous. Be very careful when you suspect this problem. Turn off all power to the appliance before you even open the door to the controls. The burned wire may be touching the frame of the heater or control panel door. Most of these major burn repairs will require an experienced technician.
- Burned wires elsewhere,
may circulate their smell with the moving air of the heater and make it difficult to locate them. Be persistent in your search. Any smell within the house will circulate with the air. It can be anything, almost.
I once discovered terribly burned wires in an outside breaker panel that was flush-mounted in the wall and the odor was drawn through the wall and through a receptacle box in the inside wall by the negative air pressure within the house and it circulated with the heater air. I looked hard and long before I discovered the origin of the smell.
TIP: If a wire in burned at a terminal of a relay, control module or other sensitive locations, chances are the part will have to be replaced. If you replace the wire and not the part, the part may fail later.
within the platform for the heater or a leaking return air duct can draw in almost any kind of smell in the closet. Seal the leakage of air and remove the items from the closet or area near the return.
may be drawn into the drain line of an electric heater. Usually with electric heat, the drain is on the suction side of the blower. If the drain is not trapped or if the trap is dry from months of winter time use, then sewer gases may be pulled right into the blower and circulated throughout the house. Not only is this undesirable and unpleasant, but is can be very dangerous to your health. Consult a good air conditioning technician or plumber. Adding a trap to the drain can be tricky and may require a professional.
If the trap is simply dry, then you can add water to it and solve the problem yourself. These traps will dry out in the winter months. Of course, sewer gas is not supposed to be present at the location where the air conditioner drain is connected, but.....
- Water seepage
from some other cause having migrated to the return air chamber or even to just the closet floor may contain odors along with algae and fungus and the smell is being drawn into the return air of the system.
- Bath rooms
cannot and should not be connected in any way to the return air system. If a unit is installed with an adjoining wall to a bath room, make special effort to seal the wall. No unit should be installed in a bathroom closet. The same principle applies to kitchens.
- Objects lodged in heating
element sections can be a source for numerous problems as well as weird smells. I have seen screwdriver handles laying on and melting every time the heat was energized. Foil tape, plastic coated duct tape and insulation are fairly commonly found in the heating element wires, also.