Best Dehumidifier for Cold Temperature Garage?

[igrout]

Hello,

Writing to ask for advice on what type of dehumidifer I should purchase to reduce the humidity in my detached garage.

My garage is 25'x32' and has a poured concrete floor. The garage is uninsulated. The walls are built pole barn style, sheeting is OSB with vinyl siding and engineered truss roofing, 2 basic windows, and a man door and an overhead door. There is no ridge vent, or spinning roof vents.

I have several classic cars in the garage, a '72 Chevy Blazer, a '65 International Scout and several King Midget microcars.

The humidity is very high 80 to 90 percent as the temperature hovers around freezing according the hydrometer, and tools not treated with fluid film have started to rust. I'm concerned that the cars will start to rust too, just bought this property in the past year.

I'd really like to get the humidity down so I'm considering a low temperature Dehumidifier that can operate down to 33 degrees F.

I'm considering a low-temperature commercial grade unit that has a defroster like the

Ebac CD35 or Dri-Eaz DrizAir 1200

or a residential Desiccant Dehumidifier like

EcoSeb DD122EA-SIMPLE Desiccant Dehumidifier or Meaco Zambezi 8-Liter Desiccant Dehumidifier

Any opinions or endorsements, a traditional Commercial Grade Unit with a defroster vs. a Desiccant Dehumidifier for a cold temperature garage like mine?

The garage with eventually be insulated, by I'd like to do something to reduce the humidity in the meantime.

Or other ideas of how to cut humidity with ventilation or other means?

 

[mike93lx]

unless there is a source of humidity in the structure, you don't want more ventilation, that will just bring in more humid air. you want to stop air from infiltrating and then dry out the interior.

seal up gaps on the walls. is the slab staying dry?

I run a normal residential unit as my garage never gets below ~45 degrees, so I can't help with a recommendation.

 

[Showkey]

Not possible to control humidity..........if you don’t have control of the “climate” in the building. Means insulation and low or reasonable air exchange rate.

Insulation and slight amount of heat .........problem solved.

The reason slight amount heat solves the issue :
Relative humidity is the ratio of the partial pressure of water vapor to the equilibrium vapor pressure of water at a given temperature. Relative humidity depends on temperature and the pressure. The same amount of water vapor results in higher relative humidity in cold air than warm air. Then add that heater dries the air gives added effect.

 

[JimNC]

I’ve been running a dri-eaz LGR in my garage for the past 4 or 5 years, highly recommend.

Of course it doesn’t get as cold here so ymmv.

 

[yeldogt]

There is nothing you can do w/o some insulation and air sealing -- it's impossible. The unit will never shut off ...

also ..the low temp are not near freezing "low temp" .....I;m not even sure my "low temp" model will work at 50

 

[finn]

A dehumidifier won’t work in your situation. It will freeze up. The dehumidifier is basically a refrigerator coil with a fan blowing over the coil and a drain pan to collect the water that condenses on the cold coil and drips into the pan.

All you can do is get the temperature up with a vented fuel burning or electric heater for the reasons Showkey stated.

It doesn’t make sense to try to heat an uninsulated building, so bite the bullet and insulate and heat.

Stopgap measures are an exercise in futility.

 

[u3b3rg33k]

or a residential Desiccant Dehumidifier like

EcoSeb DD122EA-SIMPLE Desiccant Dehumidifier or Meaco Zambezi 8-Liter Desiccant Dehumidifier

my friend has one of these in his heated garage where he washes his cars. it doesn't ice up like the regular units do. they're overpriced but they work well enough.

 

[Showkey]

In a cold winter climate like buffalo with a heated garage ..........likely with an occasional car wash a dehumidifier is not needed......saving a whole lot on the electric bill.

 

[6768rogues]

I would run a heater of whatever kind is the most cost effective and a ceiling fan or two.

 

[Jazz1]

Your only option is insulate and heat garage. My humidity stays around 40 to 50 with wood stove. If I'm not working in garage I start a fire once a day just to keep garage from getting below 32F.