High humidity in house.

[Deleted User 15924]

We have a yearly service contract to have our furnace and a/c pm'ed twice a year. On the last visit, the tech said the humidity was high and go get a stand alone dehumidifier. Tech said nothing really wrong with the furnace.

What causes high humidity in a home? Other than getting a dehumidifier (which I am going to do) what other steps can we take to bring the humidity down in the house? Thanks.

[Turkeytop]

Ventilate ventilate ventilate. Keep your basement windows partly open. When we first bought our house, the previous owners had two dehumidifiers going and the basement still smelled musty. She wanted to sell the units to us but we didn't want them. Humidity is never an issue here now. Humidity is never above 50%.

Dehumidifiers suck up a lot of power and generate a lot of heat. With adequate ventilation you won't need it.

[km1125]

On a lot of A/C systems you can run them in a "dehumidify" mode... it just runs the fan slower so it sucks the moisture out of the air without doing a lot of cooling. It would probably do a much better job of lowing the humidity in the whole house rather than a spot-dehumidifier which would be better if there's only one location you're trying to solve (like a basement).

You can "ventilate, ventilate, ventilate", but if you're in an area with high humidity outside then you're just going to be bringing that inside to fight with.

As to 'what causes it', it's either a wet basement or crawlspace, or you're bringing in humid air from outside. If you're bringing in hot outside air, the relative humidity goes up when you cool that air down to room temp. Other causes can be a pool (obviously), a lot of plants or a lot of people.

[bmw]

I highly recommend this one:

https://www.ebay.com/itm/374121738128

It's small, lightweight, only draws about 300-350 watts of power, but still sucks a ton of water out of the air, at least in my basement. Through the summer months I run it for just 4 hours every night (using the 4 hour timer setting).

Do you have an air conditioner? If not, that is a big part of your problem. If you do, the dehumidifier makes a great supplemnt.

[teetoppz28]

In our house in Florida, we have an AprilAire whole-home dehumidifier. It works wonders. I can imagine one would work even better here in the north!

Similar to this: https://www.aprilaire.com/whole-house-p ... humidifier

[Deleted User 15924]

I highly recommend this one:

https://www.ebay.com/itm/374121738128

It's small, lightweight, only draws about 300-350 watts of power, but still sucks a ton of water out of the air, at least in my basement. Through the summer months I run it for just 4 hours every night (using the 4 hour timer setting).

Do you have an air conditioner? If not, that is a big part of your problem. If you do, the dehumidifier makes a great supplemnt.

Thanks for the advice everyone.
We have central air. No basement. 3' crawl space. Don't seem damp in the crawl space. I'm going to invest in a couple of fans to pull air in and out of the crawl space.

Also I'll run the a/c in fan mode more often.

[Turkeytop]

We have central air. No basement. 3' crawl space. Don't seem damp in the crawl space. I'm going to invest in a couple of fans to pull air in and out of the crawl space.

We had a house with a crawl space. That's what I had to do. It helped a lot.

[Robert Faygo]

Check where your downspouts drain too. The further away from the crawl space, the better.