Dirty sock syndrome, DSS, results from a combination of bacterial slime and mold found on a heat pump’s indoor coil. The bacteria and mold grow on the indoor coil during the cooling season when the coil is cool and damp. The odor problem typically appears in late fall after the heat pump has been switched from cooling to heating mode. Running the heat drys out the slime on the indoor coil. The heat pump runs for longer periods as fall turns to winter. Colder weather requires defrost cycles. The indoor coil will briefly become cool and damp when a heat pump enters a defrost cycle. It then switches back to being hot when the defrost cycle terminates. It is the switching back and forth from heating to cooling that causes the bacterial slime and mold to emit a foul offensive odor. DSS is not believed to pose a health risk, to healthy persons, but it can certainly make a home an uncomfortable place!
The good news is that odor caused by DSS may be eliminated with professional use chemicals developed especial for this purpose. Marty Singer has been using the same product for many years with near 100% success rate at eliminating the odor of DSS. Give us a call. We will be happy to answer any questions regarding DSS or other heating/cooling issues that you may have.