Dehumidifier: Helper or Energy Hog?

[rh77]

I recently inherited a free-standing dehumidifier and gave it a whirl.

The control knob is roughly calibrated to ambient humidity, and it has a low/"quiet" fan speed selector.

It's hooked up in the basement and drains into the sump well. The knob vs. a humidistat shows 60-70% humidity, but no fogging of windows or dampness is noted.

So, is this thing a good supplement to reduce the burden on the Central Air system, or just a device for musty, damp basements?

RH77

[ffvben]

i have mine 65-70% installed in the basement. that thing gives off lots of heat but keeps the basement nice. it used to be at 50% but it ran a lot more and heated the basement up in summer, dryer but hotter( no ac down stairs). that keeps the moisture off the elec box, that keeps corrosion down inside the box too. and i think it helps lower any mold growth too.

[Erdrick]

The following is not really related, but I feel that it needs to be said anyways.

My dad built our current house using a poured styrofoam basement. In other words, a company came in and built a foundation out of, yep, hollow styrofoam. After this was complete, they continued to pour concrete into said styrofoam. The result was a warm basement in the winter, and a cold basement in the summer... with our without central A/C or heating. All of this in Michigan. Oh, it is a walk-out basement with lots of windows (that have shades for the summer months).

To tie this in with the OPs question, we have NO humidity or condensation whatsoever. Our previous house, with a traditional poured concrete basement was (if my memory serves me) always damp, pretty much year round.

Point being: make your basement from styrofoam and you will never have to worry about humidity problems again!

[Hockey4mnhs]

idk this would help me alot if somone knew for sure because i have mine running right now. it helps but it does seem like it would use a lot of energy

[WisJim]

I ran our dehumidifier this summer for a couple of weeks after we had a lot of rain and some rain managed to get into the basement. It ran almost 24 hours a day, and drew about 300 watts, but made the basement warm faster than it made it dry. It also increased our electric bill for that month to the highest it has been for years. I thought that something had gone wrong on the place, or there were lights on somewhere that I didn't know about, until I put the Kill-A-Watt on the dehumidifier and found out what it uses. And, due to power factor, it uses over 500 volt-amps, which affects the actual power usage from our battery/inverter system.

I think that a small air conditioning unit might be a better choice, for someone buying new, as an A/C would cool as well as dehumidify, and you usually use the dehumidifier in the summer when you don't really need the heat from the dehumidifier.

We were lucky and had a few nights of below average temps that were also dry, so we opened 2 basement windows late at night and ran a fan to circulate dry cool air to dry out the basement and cool down the root cellar.

[brucepick]

My parent's house has a walk-out basement that's finished inside. Guest bedroom, living room, bath, more.

Always was damp as heck there. Always had a demidifier running which helped noticeably. Was quite cool even with it running.

In their case it's mostly a condensation problem, since the walls were always quite cool and the air is damp in that locale. Not a seepage probem in their case.

They redid the bathroom with styrofoam applied to the exterior walls, then wallboard and wallpaper over that. This helped that room a whole lot. Moral of that story is, if you have a moisture problem in an existing basement, consider styrofoaming all the walls before you think about dealiing with the floor.

[baddog671]

We have 2 dehumidifiers in our basement. It isnt damp down there, but I have a classic car I like to keep from rusting and it keeps the wooden French doors from swelling and creating shutting issues..

[WisJim]

Those darn classic cars!! We are working on putting radiant heat (solar heated hot water of course) in the floor of part of our existing pole shed so we have better storage for the 1971 Honda N600 and the 1965 VW double cab pickup. Maybe not what my generation usually considers classic cars (I think more of Packards or other huge majestic machines from the 1920s or 30s), but I am sure a younger generation will consider them classics.

Of course, it will provide heated workshop space, too. I like the idea of low intensity heat to keep things dry instead of the refrigeration system of a dehumidifier, but heating the basement floor in the summer to keep it dry is counterproductive if we also want it reasonably cool.

[lancek]

I keep one in my gun room, guns+rust=bad Not real concerned about the cost there...

[CoyoteX]

I run a dehumidifier in my house and keep it as dry as possible. Last year was the first year I ran it and my gas bill was lower than usual, part of it was the dehumidifier generated some heat but most of it was because drier air doesn't pull heat out of your body as fast as damp air so I was able to run the heat at a lower temperature without feeling the least bit cold. I don't run it in the summer and just leave all the windows in the house open with fans so it won't help in the summer. In the winter though it is noticeable if I forget to dump the water out and it is off for 12 hours or so, the house feels colder and uncomfortable. I keep it set at 30% in the winter and it runs for a week straight to get the house down to that in the winter to start with then it cycles prob 75% of the time running.