I thought I saw a recent thread relating to this but my searches have been unrewarded.
I have sectioned off a portion of my basement as a wine cellar as I am not prepared to invest in a true cellar in this particular house. I have used an air-conditioner in a window to maintain acceptable temperatures. Since it’s not properly insulated, I run a de-humidifier at 50-60% to avoid moisture issues for the greater basement. Problem is, after 6-12 months, the AC unit is building up mold. I’ve seen procedures to clean this up but getting the unit out and back in is no easy task.
Anyone have similar experience or know of a way to prevent this from occurring? My replacement costs are starting to mount.
Hi Greg,
The air going across the coils in a window AC unit is usually around 40F. That’s cold enough to pull moisture out of even 50% humidity. So the cooling unit is probably still dehumidifying the air constantly when it runs. When it runs it’s generating condensate and the humidity stays in the line or the tray where the mold can build up. If the line can drain well it will slow down mold buildup, but those window units are notorious for building up mold and even algae in the drain tubes.
Double check that it is sloped properly and that the line itself is not clogged. Given the time frame you listed it’s probably draining okay and just took its time to start the molding. There are a few calculators on the internet that show temperature and humidity and how long it takes to mold. at 70% RH and normal cellar temperatures I think I remember it being 6 months or so and that’s consistent with a lot of condensate keeping the drain pan wet.
As for cleaning the units themselves, I’m not sure what to do. My cellar is passive and I don’t have those window units. A strong vinegar or ammonia spray should kill the mold without using bleach (a no-no in the winery, probably okay for cleaning the unit away from the wine bottles). Another thing to try is leave the fan on constantly. That extra air movement even with the compressor off should help dry out the condensate pan and coils.
I kinda doubt that anything anyone can tell you on Wine Berserkers is gonna alter the reality of PV = nRT.
You could set up sprayers to mist your cellar with a chlorine solution, and that might kill the mold in the AC unit, but, as above, you might wanna investigate a chemical called Tri-Chloro-Anisole before you try that method.
Back in the glory days of eBob, Pierre Rovani was insistent that mold on an old bottle was a GOOD thing for collectors [if not for speculators & flippers & auctioneers], because mold tended to prove that the bottle had been stored in a cool dark moist place, where the cork never dried out and the glass never saw sunlight.
My guess is that you’ve got mold in the basement from other sources - your need to run a dehumidifier suggests that you’ve got moisture - and the AC is just accumulating the mold on it as well, where it’s easy to see (I’ve seen black crud on the cooling vent on mine, but not much). My basement is generally below 35% humidity year round (and that’s in DC) because it’s dry in winter and conditioned in summer.
So I’m not sure the problem is the AC unit itself, which is perhaps good news if true. Bad news if true - you have a mold problem in your basement.