Condensation on larger boats

[OS2Dude]

On my O'Day 23 condensation during the cooler months never seemed to be an issue. There was a little, but not really noticeable. (I did a full winerization to her each fall and had to wait until spring to use her again.)

This will be our first winter on our 1985 Catalina 30. It has an A/C with reverse heat that we are leaving on. We went up to the boat for some sailing, and when I went below I thought something had sprung a major leak. EVERYTHING was soaked. The cushions, the rugs, everything everywhere was wet to some degree. In the morning when we awoke we saw the cause, condensation was over every window and some portions of the cabin roof. (Especially the vBerth) There were heavy large drops of water that were dripping all over the boat.

QUESTION: Is keeping the heat on a bad idea? (Boat is in Lake Lanier, outside of Atlanta GA.) It does get cold here at night (Usually mid-30s, but once down to 6 degrees) during the winter, but we want to be able to go out on her when we have the chance, so we don't want to do a full 'WINTERIZATION' like I did with the O'Day. Are the chemical desiccants a viable idea? I've seen them used in houses, and they can be a bit of a mess. What do others in marginal temperature areas do so they can still sail during the Fall/Winter months? Am I wrong to think keeping the heat on will make winterizing the fuel and engine, fresh water, etc unnecessary?

Thanks!

 

[woodster]

i think the heat is causing your problem ...you need to have air circulating in the cabin .....if you heat it too warm inside you are creating a green house ...along with the fact that there is not much insulation in the construction of your cabin cap...i used a thick pile marine carpet to make a headliner in my boat to help that and keep from having to fair and paint the inside ....if you have a deck vent lick a narco solar it will move air through and slow that condensation down some ...if not put a fan in there and leave it running to keep the air circulating inside and set the t stat at 45 to 50 degrees and see if that helps along with the fan

 

[centerline]

air circulation and ventilation is necessary.
the fact that you have that much moisture indicates you have a wet bilge.
usually a wet bilge can cause a smell with a damp feeling throughout the boat, but if there is dripping moisture inside boat that has not had someone in it for awhile, and the upholstery is extremely damp or wet, it is a good indicator that there is a leak into the living space of the boat somewhere...

 

[woodster]

you can always use a dehumidifier on the boat in your case but get one that has a large capacity collection box or drain hose

 

[thinwater]

"... get one that has a large capacity collection box or drain hose."

On smaller units that means tapping for a small hose barb or using a small compression coupling as a bulkhead fitting. Not difficult, that is how I rigged my Evadry 2200.

 

[Kings Gambit]

QUESTION: Is keeping the heat on a bad idea? (Boat is in Lake Lanier, outside of Atlanta GA.) It does get cold here at night (Usually mid-30s, but once down to 6 degrees) during the winter, but we want to be able to go out on her when we have the chance, so we don't want to do a full 'WINTERIZATION' like I did with the O'Day. Are the chemical desiccants a viable idea? I've seen them used in houses, and they can be a bit of a mess. What do others in marginal temperature areas do so they can still sail during the Fall/Winter months? Am I wrong to think keeping the heat on will make winterizing the fuel and engine, fresh water, etc unnecessary?

Thanks!

Dude, You might find some of your answers in this thread of a few months ago as well, when it gets into the discussion of condensation.
KG

http://forums.sailboatowners.com/index.php?threads/cruising-in-colder-waters.174935/

 

[JoeWhite]

For ventilation and fresh air circulation I assembled 4 X 3 1/2" computer fans 12VDC and placed it on a port. It draws fresh air from outside and forces it inside. I leave the V-birth hatch cracked open so that air may escape. Works great. The power for the 12VDC is supplied by a 12VDC adapter that is plugged in to the shore power.

 

[markwbird]

Ventilation plus heat is the cure. I installed a Nicro solar vent and a small space heater. Dry as a bone inside. Your situation sounds like you have water coming in creating a humid interior which then condenses on the cold surfaces. You may indeed have a leak. All of that water is going to cause a serious mildew issue if you do not address it quickly. Ventilate and warm the cabin and then find the leak.

 

[JEFF POPE]

This has been the worst few months ever for condensation for the area, A simple fan usually does the job, but not lately.

 

[seadaddler]

I added a small dehumidifier and added a drain hose into sink and so it runs
24/7 with out shutting off and it was around $40 Dri Air I think makes it.
I do have AC and built in dehumidiefer but this works real good and also run
fans inside to move air around.
nick