humidifier problems - condensation + ice

spots · #1 01-23-2013, 10:50 AM

Recently got a hybrid and am trying to keep it in good condition with a humidifier. I have an evaporative humidifier that keeps the bass room at 40% RH.

I've noticed condensation on the windows which I try to keep on top of by wiping it down. The windows are aluminum (I think) double-hung windows (likely from the 70s).

Last night was really cold and I woke up to find ice had formed on one of the windows near the seams where the window meets the side frame.

This is troubling me. I'd like to keep the room properly humidified but I'm worried about mold developing and damaging my windows. Has anyone dealt with this before? Could I reduce humidity to 35% (danger zone) and still be ok?

Eric Hochberg · #2 01-23-2013, 11:05 AM

I think you can reduce to 35% Your hygrometer may also be reading low, as mine does. You can find an easy test for it online.

RSBBass · #3 01-23-2013, 01:57 PM

Freezing condensation is normal with single pane glass (or old double pane). You probably would still get some at 30% R.H. Aluminum is a poor host for mold but if you see any signs, you can wipe the window frame down with a solution of 1 cup to one gallon of bleach.

Matt Ides · #4 01-23-2013, 02:30 PM

We have been in the negatives here and old and new windows will get condensation inside.

gandalf1 · #5 01-23-2013, 02:48 PM

+1 on the cold + condensation.

Condensation on a window (or similar cold surface) is not a strong indicator of overall room humidity. As mentioned, condensation/ice will form at any humidity > 0% if the surface is cold enough. Technically what happens is the air near the window surface is cooled below the dew point, at which point the air can no longer contain the moisure it has, and some condenses out. If the surface is cold enough, this condensate will freeze.

Although strictly speaking this mechanism will pull some humidity out of the air, it is insignificant to make a serious dent in the overal room humidity. To appreciate this, just observe the gallons of water removed from a basement dehumidifer over any 24 hour period.

It's still a good idea to monitor the humidity, however. Keep the humidity meter near the bass. Keep in mind as well that most humidity meters have an accuracy of +/- 4% or more (despite what the instructions say). Meaning that if the true humidity were, say, 40%, the device can read anywhere from 36% to 44%.

If you do use a humidifier, place it far from the bass and humidity meter to avoid producing an artificially high reading. A fan, even on low, will do wonders to distribute moisture evenly through a room.

-Jon Longtin

spots · #6 01-23-2013, 03:21 PM

Right now I have a humidifier with a built in humidistat. It cycles on an off to try to keep the humidity at a set level. The humidifier is on the other side of the room from the bass. I also have a hygrometer next to the bass (cheapy off amazon) which I use to track the room humidity.

I guess I can expect the condensation. The windows themselves aren't getting icy, it's the channels that the window panes slide in. They are getting very icy (see picture below). The windows are pretty drafty and single pane. Do you think weather stripping in the channels would help? Or should I just cover the windows with that 3m plastic wrap?

Champagne · #7 01-23-2013, 05:11 PM

Throw a little sugar and food coloring on it and lick it on up. :P

Seriously, I have the same type of windows and the same thing happens. I however do get little specks of mold since the metal has been painted. This surfaces in the summer. I use a clorox bath cleaner spray and wipe it which usually does the trick and it doesn't come back for a year or 2.

Mold does suck, especially if you are sensitive. It is also in the air we breath during the warmer months. Not to diminish the threat, but the tiny bit I get I don't worry about. I have seen mold issues to worry about.

Champagne · #8 01-23-2013, 05:14 PM

And remember, this case is solely on my windows. Not on my walls surrounding them. If my walls were dripping or showed signs, it would be a different story. I think this is par for the the type of window. Metal conducts heat and cold much better than stone or wood walls.

fdeck · #9 01-23-2013, 09:57 PM

We've got a whole-house humidifier going, but for some crazy reason, half of the tuning pegs in the house (2 violins, 2 cellos) let go today. I don't understand it.

longfinger · #10 01-23-2013, 11:04 PM

Condensation on the inside window is common in winter. If it is very cold outside, the freezing on the inside is also common. The way to deal with it short term is simply turn up the room heaters (under the windows for this very reason... now it makes sense right?) to keep the window warm enough to prevent the freezing, and perhaps even the condensation. That draws quite a bit of power and can get expensive though.

spots · #11 01-24-2013, 05:48 PM

Update: In order to cut down on the ice I installed plastic sheeting on the windows in the bass room. Hopefully that will reduce or eliminate the condensation and icing over. At the very least it will make the room warmer.

I also decided to test my hygrometer using the salt test. This method allows you to create a 75% RH environment and see how off (or on) your hygrometer is. It takes a while (24 hours) so I'm still in the process.

Here's a link for how to do the salt test.
http://www.youtube.com/watch?v=amSMJ2pUIdE