Dehumidifiers for over winter

[jasonthegreyhawk]

We are going to be storing our Greyhawk on our property over the winter. I will likely use it from time to time as an overflow for my office (I work remotely) so it will likely be connected to power over the winter. If not, it also has the solar power running.

My question is, given the importance of preventing moisture should I just run a residential dehumidifier inside? I wouldn’t mind emptying it once a week or running it fairly low to do so less.

I know there are some RV specific options like the unit that slightly warms the air but is it better to just go ahead and run a true dehumidifier if I can do so easily?

[cpd1343]

A dehumidifier will not work well if at all in below freeing temps. For low temps I use DampRid.

[jasonthegreyhawk]

That’s a Duh on my part - I didn’t even think about the fact the temp will be below freezing. Thanks

[craigav]

While some may disagree with me (you may want to research this a bit), you really don't need a dehumidifier in an RV that is not being heated or lived in (as long as it is dry inside to start with). The interior moisture concern is more associated with having a difference in the temperature and humidity level inside the RV than what is outside the RV. In other words, a heated RV with one or more people in it for any extended period of time creates humidity (raises the dewpoint) and even more so if cooking and showering. When the interior dewpoint temperature (based on the humidity) becomes higher than the wall and window temps then sweating occurs and that is what you need to avoid. If the RV is at the same temp (no heating) and no one is inside adding humidity then there will be no sweating on the walls and windows. On the other hand, if you (anyone) was to stay inside for many hours and especially when running the heat, then the dewpoint (humidity) could rise high enough to cause sweating on the walls and windows in particular when the outside temp is a lot lower. However, in that case you could certainly use a dehumidifier as the indoor temp would be (hopefully) well above freezing and the dehumidifier itself would add a bit of heating which would be helpful. ~CA

You can calculate the dew point as many digital thermometers show humidity and temp only, however there are some such as this one that calculates the dew point for you. If for example you find the dewpoint is 60f and the outside temp is 40f (or simply lower than 60f) then you will know that moisture will start forming on uninsulated windows and perhaps the walls depending on how well the insulation is. (any dewpoint reading higher than the outside temp is when moisture forms).

https://www.amazon.com/Geevon-Wirele...s%2C370&sr=8-6

[norty1]

I run one all the time when my rig is at home and not in use. Not in freezing weather! Mine is a regular household unit with a 1.5 gallon reservoir. When it fills, dependent on humidity, we manually dump it.

It does a great job of reducing humidity.

[JFlightRisk]

I put an Air-Z-Dri in the kitchen sink for over the winter. The pellets in the upper basket absorb moisture and it drops into the cup below. I believe the pellets are calcium chloride, and dissolve as they work. Here in NY one basket of pellets last the winter.

https://www.drizair.com/

[norty1]

Originally Posted by JFlightRisk

I put an Air-Z-Dri in the kitchen sink for over the winter. The pellets in the upper basket absorb moisture and it drops into the cup below. I believe the pellets are calcium chloride, and dissolve as they work. Here in NY one basket of pellets last the winter.

https://www.drizair.com/

WE tried those years back but would run thru one a week in 85% humidity.

[jasonthegreyhawk]

Definitely different in the Northeast than the South

[hoppers4]

I've gone through multiple dehumidifiers over the years and finally found one that really works. It's not a compressor dehumidifier but a desiccant dehumidifier. Here in the Pacific Northwest I get about a half gallon of water a week out of my rig in the winter. And the best part is that it will work down to 32 degrees and then shut down. Humidity is very low during cold weather anyway. It does give off a little heat as it runs a heating element as part of it's operation. It uses about 500 watts which I believe is less than a compressor dehumidifier. I set mine to keep the humidity down to around 50%. Oh, and it's very quiet also. Just fine to run it if you're camping in humid weather or trying to keep the humidity down while cooking or showering. BTW, the Ivation is a true dehumidifier, just works on a different principle.

Here's the link. https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1

[hoppers4]

Originally Posted by JFlightRisk

I put an Air-Z-Dri in the kitchen sink for over the winter. The pellets in the upper basket absorb moisture and it drops into the cup below. I believe the pellets are calcium chloride, and dissolve as they work. Here in NY one basket of pellets last the winter.

https://www.drizair.com/

I'd be interested in what the humidity in your rig is using the drizair. A lot of thermometers have humidity indicators also so it'd be interesting to see if they really make a difference.

[JFlightRisk]

Originally Posted by hoppers4

I'd be interested in what the humidity in your rig is using the drizair. A lot of thermometers have humidity indicators also so it'd be interesting to see if they really make a difference.

I might be able to come up with a comparison between the day we wrap it up for the winter, and some point down the line if I can get into it. We have a clock inside with a humidity gauge in it, as accurate as it might be.

The Dri-Z-Air does pull moisture out, and depending on the year will be either completely dissolved, or a small amount of pellets left. I will try my best to remember to get a comparison to post here. It'll depend on old man winter.

[pconroy]

Originally Posted by jasonthegreyhawk

Definitely different in the Northeast than the South

I was going to suggest heading out to Colorado this winter for a visit. Our winter humidity is usually quite high for us... Like 0.0000000000000000000001%

[MEILI]

I run canisters and hanging bags of damp-rid here in NH. I'm not sure if it's needed or not but the bags do have a good amount of water in them come spring.

[Rock]

I run one at home all the time. Set at 55% it fills every two days.

[Johnynorthland]

I use 4-5 gallon buckets of damp-rid in my 28’ class C. Works well!

[Bob Pope]

Instead of a dehumidifier that requires electricity, a drain bucket or drain hose we use the 'Damprid' Bucket. No mess, no flood and put anywhere on a flat surface. Lasts for a month or two depending on heat and moisture. We are in the South too.

[Johnynorthland]

If I were to use a dehumidifier in my RV, I would drain it into a sink or shower and keep my grey tank valve open, but I would put a screen over the outlet of the dump valve outlet! Don’t want critters getting in!

[Rock]

Gray tanks can stink worse than black. I am not gonna drain my gray under my Rv carport ( gravel floor but enclosed 3 sides). I just empty it every two days. And I have it sitting in the shower just in case.

[TGoldsbury]

|If I were to use a dehumidifier in my RV, I would drain it into a sink or shower and keep my grey tank valve open, but I would put a screen over the outlet of the dump valve outlet! Don’t want critters getting in!|

Above is what I do, but found out my dehumidifier goes into error mode if it gets over 90 degrees, which in Florida is everyday. Had to set the AC to 85 to keep the dehumidifier working, but then the AC keeps the moisture down so don't need the dehumidifier!!!! May try the damprid in the summer and leave the dehumidifier for the winter.

[mikeplaneguy]

I run a small ceramic space heater in mine over the winter. Costs maybe $30/month to keep it 60 degrees. It's real nice to take a break from shoveling snow in there haha.



Also have a small dehumidifier for the summer months when I don't leave the A/C running.