It is often thought that Freon in an air conditioner can give off an odor. This misconception can be attributed to the fact that most Winnipeg homeowners have their furnace in a basement area where the filtered or unfiltered air can leave small deposits on the (evaporator) cooling coil that is hidden inside the furnace plenum. Freon or refrigerant is odorless but becomes toxic if exposed to an open flame, as being burned.
Here is an example of a recent customer enquiry and my response:
My house smells like bleach since starting the AC. Given that it seems to coincide with starting it up for the season I was wondering if this is a common problem. Is this common? Something that can be fixed?
Sent from my iPhone
This is not uncommon. The evaporator (cooling coil) sits in the air stream above your furnace and will collect any form of microbes in the air and eventually build up enough deposits that in a dry state (heating season) produce little odor. Cooling season however will produce condensation on the cooling coil and wet any deposits sitting on the coil surface. Depending on the type of deposits, you may notice a variety of different odors especially during the first few cooling cycles.
If the odors persist then a professional coil cleaning may be the only solution.
Laundry room chemicals, pet odors and musty basements are the most common reasons for a smell that becomes noticeable during a/c start-up.
Hope this helps.
Here are some sensible preventative solutions for the most common of these situations.
- Laundry room chemicals should be kept sealed when not in use.
- Pets dander and of course urine and fecal matter should not be left exposed to the air you breathe for any length of time.
- Musty basements should have return air vents at floor level and have a continuous low speed furnace fan operation. A fresh air intake can also be added to provide new outdoor air directly to the furnace return duct.
For technical information on many more HVAC topics, Visit us at www. TMS2020.com.