In the world of air conditioning repair, you generally known that furnaces have strange odors when they are defective, but did you know that air conditioners can smell "off" when they are defective or dysfunctional too? In fact, it may surprise you to learn that how your indoor air smells or how the air conditioning unit outside smells can be a strong indicator of a specific problem with your air conditioner. So, without further ado, here are air conditioner smells that tip you off that something is not right with your air conditioner, and what those smells mean.
The Smell of Something Rotten
A rotting odor, if it is not coming from your bathroom, your kitchen garbage disposal, your dishwasher, your garbage cans, or your teenage son's bedroom, may indicate that something got into your A/C's outdoor components and died. It can also indicate that something got into the ducts that come from the A/C unit and head up into your home. After you rule out all of the other possible causes of something smelly and foul, flip the thermostat from A/C to heat and see if the odor is still coming through.
If it is, the rotten smell is coming from the shared ducts of the furnace and air conditioner. If the smell dissipates into nothingness, then the rotten odor springs from the A/C components outside the house. Your HVAC technician will have to open it up, find what is rotting, and remove it.
The Smell of Stale Ice
People say that ice has no smell. In truth, they are partially correct. However, both ice and dry ice can attract and accumulate odors of the things around them that they are trying to keep cold. This stale ice odor common to ice makers in refrigerators, and the thick frost covering the insides of a freezer chest, is the same odor you will smell coming from your air conditioning when something is wrong. The stale ice odor coming from your A/C could be that it is running low on refrigerant, or worse, leaking refrigerant. Your repair technician will have to check for leaks, and then replace those parts. If there are no leaks, then the technician will check and fill the refrigerant as needed.
If you smell a burning odor when you have the air conditioning on full blast, you should A) check the outside components to make sure they are not on fire, B) check the furnace area and ducts in your home, and C) turn the A/C off and call a technician. If something smells like it is burning, it probably is. You want to stop that right away and get emergency HVAC help.