[dmrlook]

Hello everyone - I have a humidifier question - actually a few. This will be my second winter in my house. We have a natural gas furnace. There is no humidifier. I've noticed a small amount of condensation on the windows, and therefore assume I don't have a need for a humidifier. However, my wife thinks the air is dry in the winter (I don't notice it, but others have). Does it make sense that the air could be dry yet I still have small amounts of condensate on the inside of the windows (only a few windows mind you).

Question 2: Should I need to buya humidifier, any suggestions on what to look for. We have a two story house with a finished basement. The furnace feeds all three levels. We have only one thermostat on the main level, and there is only one zone.

Question 3: Is it true that the humidifier should be installed on the cold air return? If so, will it matter that the humidified air will be passing through the air filter.

Thanks for your help,
Rob

[labman]

The amount of condensation on the windows depends on 2 things, how much humidity is in the air, and how good the windows are. Our ''old'' house compensated for the single pane, metal frame windows with marble window sills. Our current house has wooden windows and storms. I have caulked around the storm frames, and they seal fairly well. I have also done enough other caulking, etc. to keep the humid, inside air inside. Our house stays reasonably humid without a humidifier of much condensation problems.

I think humidifiers usually go on the supply side where the hot, dry air picks up more moisture. Before I tightened up the house, I had one of the humidifiers that is driven by the movement of the air. No electrical connection needed. Fewer moving parts to maintain. Humidifiers are a nuisance, tending to lime up.

[NorthernHeat]

Labman I think said it all. Realitive humidity is a measurement of how much moisture air can hold at a specific temperature. Then there will be a dew point based on the current realitive humidity. So, if it is 70 degrees in the house with a humidity of 20% which is uncomfortably low for most people, the moisture will reach saturation temperature, in other words condensate at lets say 55 degrees. You can find tables and charts on line that will tell you exactly. My point is a window doesn't need to bet super cold to form condensation even with dry feeling air. Note as it gets colder outside the air inside must get drier, even with a humidifier, otherwise this humidity will start to condense in many places you don't, want including inside walls and attics and in the insulation itself.