de-humidification

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No one has mentioned a problem I had when I put a GE 30 pint on my GB 42. Put it on the galley counter top with the hose to the sink. Powered it up and came back the next day and the boat was 90+ degrees inside. Not from local temps but from the dehumidifier running. Wow did it make it hot in there. Took it back to HD and haven't put anything back on. I don't have an humidity issues ie. mold/mildew but would like to lower it "just cause". I have been meaning to go the Parks route and get one of the Eva-Dry units he mentions but haven't gotten there. With everyone's positive results using the bigger ones and no mention of any high temps maybe I had a bad unit or something.
 
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No one has mentioned a problem I had when I put a GE 30 pint on my GB 42. Put it on the galley counter top with the hose to the sink. Powered it up and came back the next day and the boat was 90+ degrees inside. Not from local temps but from the dehumidifier running. Wow did it make it hot in there. Took it back to HD and haven't put anything back on. I don't have an humidity issues ie. mold/mildew but would like to lower it "just cause". I have been meaning to go the Parks route and get one of the Eva-Dry units he mentions but haven't gotten there. With everyone's positive results using the bigger ones and no mention of any high temps maybe I had a bad unit or something.


I’ve used the 30 pint dehumidifiers for years. I’d leave them running 24/7 when we weren’t on the boat. They do create a small amount of heat but I’ve never felt it was an issue. Another way to look at is is that I don’t think they put off any more heat than the refrigerator does. So if the unit you have is putting out a lot of heat then, while unlikely, maybe you have a defective unit?

FWIW, as I’ve mentioned before that the last two years I’ve switched to using two large Eva-Dry and one small Eva-Dry dehumidifiers. The three of them combined aren’t as effective as one 30 pint compressor dehumidifier. However, they are much quieter and smaller. We can leave them running and leave them in place when we are on the boat.

The only problem with the 30 pint dehumidifiers are that they are large, heavy, and loud. On my boats, there isn’t a great place to store them while underway that isn’t also underfoot. We would place it in the second cabin which was fine when we didn’t have guests. The advantage of them is that they are incredibly effective. Unlike the Eva-Dry, they don’t tend to freeze up in cool weather. During the winter months a 30 pint will keep my boats interior below 50% humidity even when the outside humidity is 99% and windy. This is in a boat that isn’t sealed up or wrapped. The 3 Eva-Dry units will only keep it around 65% under those conditions.
 
No one has mentioned a problem I had when I put a GE 30 pint on my GB 42. Put it on the galley counter top with the hose to the sink. Powered it up and came back the next day and the boat was 90+ degrees inside. Not from local temps but from the dehumidifier running.


Never been an issue for us - in the RV or the boat.
 
Yes, the big dehumidifier heated up the interior of my trawler. Heck the little one I use on this boat does too. However, since I only use a dehumidifier when the boat is unoccupied for periods of time over a few days, it never occurred to me that was a problem. Hot and dry way better than hot and humid here in Florida.
 
Any dehumidifier will put whatever energy it is using into the space it is dehumidifying. For a 30 pint unit that's like running a 500 watt heater. In Florida that could be a problem. In the PNW it is likely welcome.
 
Boat is actually to dry

I was worried about winter condensation myself after reading so many posts about it
but when I first got her I gutted the foc'sle and put insulation up to r value of 12,then put her
All back together,I have 2 1500 watt space heaters,one on oil pan and other in salon,I leave one of the engine room access doors out,and have a Chinese diesel heater that feeds foc'sle and salon,on the coldest night so far did test and got interior up.to 90 degrees,had a few cool spots but fixed them with a few small fans,but if anything the boat is super dry,I can tell because it dries out my hair and skin,if anything almost considered adding humidifier in foc'sle plus I made sure of proper air exchange and ventilation which I believe
worked wonders,well have to wait and see this summer with the humidity,but boat will be air conditioned
 
For smaller boats that can be buttoned up tight a partially sealed container bottle or two of mustard gas has been known to work.

Of course one has to remove the containers and ventilate well before using the boat.

Although the formula for mustard gas is common and well known , I prefer not to publish it.
 
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