Condensation Problem in a 22 Cruiser.

[ssobol]

It may depend on what the tube is made out of. It is possible that the warm air from the cabin will maintain the tube at a warm enough temperature to prevent water condensation from occurring in the tube. The tube would need to be of sufficient thermal mass or length to prevent that from happening (perhaps fins on the tube to remove the heat). You'd also want to seal the cabin so no (or limited) humid external air is admitted.

 

[robhwa]

Do not "seal up" the boat, except to prevent liquid water from running into it. It sounds counter-intuitive, but you need to bring cold air into the boat and put warm air from inside the boat to the outside to reduce humidity in the boat if you only have a heater. In the rainy PNW, the outside cold air will almost certainly have a lower absolute humidity (water in air) and higher relative humidity (water actually in air/water possible in air) compared to heated air in the boat. For instance, if you bring in air at 50F (10C) and 100% RH, the air would hold about 8 g water per kilogram of air. Air at 77F (25 C) and 100% RH 20 g water per kilogram of air. That heated air would now have a RH of 40%. Condensed water on the surfaces of the boat would evaporate into that air. If that air is not put outside the amount of water (on surfaces and dissolved in air as humidity) will not change, except that it might go up because of the water in your breath and perspiration. You absolutely MUST get some of that warm air outside and bring more cold air inside. This is why following the posts that recommend ventilation will reduce water in the boat, and the posts that recommend sealing up the boat will not.

 

[Marco Flamingo]

the only way to help remove the moisture is ventilation

Which is why I've never had a moisture problem even with two people sleeping in the Limpet's tiny V berth. The back of the CD 16 cabin probably doesn't seal up enough to trap all of the moisture. I try to help it by leaving the hatch cracked open, or a couple of snaps loose on the cockpit cover if it is on. I sometimes get condensation on the windows, but nothing dripping off the cabin top or a wet hull soaking the bedding.

Warm bedding might be our secret. We use a down comforter. Good to the low 40's. If it's colder than that, it's time for jammies. That allows us to leave everything open (sometimes with mosquito netting) if the cockpit cover is on. The only moisture issue I have is rain through the hatch.

I can turn on the Espar from the V berth, so I don't get up until the cabin is warm-ish.

Mark

 

[hardee]

I mostly single hand so that may make some difference, but I rarely have humidity condensation inside the boat. That is probably due to a couple pf things. 1. I keep some ventilation available --> the forward hatch is always open at least an inch AND the center window is also open about the same. Both have a "sort of" latching ability at about that point so that is where they go. 2. I use a CPAP device (without any humidifier), and that device is running a small "fan" that promotes air circulation around in the birth. 3. I don't cook in the boat, so no steamy kettle to deal with.

I think the most important part is the ventilation. If it is not raining I also leave at least one side window open. If I'm on a dock, it is the one away from the dock. If at anchor, both sides are open about 3 inches. The Wallas is not on over night.

Harvey
SleepyC :moon

 

[colbysmith]

Back from the C-Brat gathering at Hontoon, where I saw one of our fellow Brats boat (Two-Bears with Chuck and Penny), where they had a fellow install automotive interior to their cabin walls. The guy did a great job and it looks quite nice. Both Chuck and Penny said their boat now stays dry. I was ready to stop by whoever did their interior on my way out to the upcoming Friday Harbor gathering, (in reality, checking around here locally to see if anyone can do that kind of work), but decided I should maybe throw it out there for more opinions before doing this, just to see if anyone else has done the same with luck. While I do notice some difference in keeping a few windows a pinch open, this doesn't always work. Times when there is rain or high moisture outside or when it's below 40 degrees! I may look at that SC1000 paint also, that was mentioned earlier. (Or perhaps in a different thread....I'm reading several....) BTW, I also routinely run a fan at night, but that doesn't seem to help. And I've done the combustion air intake for my Webasto heater both ways. (Using inside or outside air.) I also have two solar vents on the boat that I run in exhaust mode at night. Colby

 

[thataway]

I have done this interior wall finishing by using closed closed cell neoprene foam (like wet suit material). PVC closed cell foam ( fish blanket) in Alaska hardware stores. I put fabric or very thin laminate on the inner ( boat inside ). Another way is to use door skins with boat headliner material, leaving an air space between the fiberglass and the liner material. There is the “mouse fur” type of material used by companies like Bayliner. I have seen it mold. I have seen the perforated material separate from the vinyl, I ave seen mold develope on this inner foam.

Glue on is the fastest and cheapest route.

 

[ssobol]

I may look at that SC1000 paint also, that was mentioned earlier. ...

I did the SC1000 paint (3 coats) followed by 3 coats latex house paint. I did not use my boat in condensing condition before this was done so I can't compare. However, this treatment did not eliminate condensation in my boat. It may have reduced it, but in cool/cold conditions the inside surfaces of the cabin and v-berth still get damp. We don't have any dripping so maybe that's something or maybe we just don't experience the same level of dampness as the PNW.

However, this treatment did improve the looks of the interior a lot (IMO). It smoothed the surface out some and the paint color chosen lightens the interior quite a bit. Between the prep, masking, painting, and clean up it took about 9-10 days to do the interior (which involved painting all the insides of the exterior surfaces, including inside compartments and cabinets).

This gallery shows the interior of my boat: http://www.c-brats.com/modules.php?set_ ... _album.php

 

[AstoriaDave]

To decrease condensation to a minimal level you have to increase the R-value of the hull/added insulation. A few coats of paint will not do it. You need to add a layer of foam insulation, per thataway's methods. I would guess a quarter inch or three eighths thick closed cell foam would work most summertime temps.

And then, circulate air over those surfaces, venting to the outside, with a window open somewhere for makeup air.

 

[colbysmith]

I did the SC1000 paint (3 coats) followed by 3 coats latex house paint. I did not use my boat in condensing condition before this was done so I can't compare. However, this treatment did not eliminate condensation in my boat. It may have reduced it, but in cool/cold conditions the inside surfaces of the cabin and v-berth still get damp. We don't have any dripping so maybe that's something or maybe we just don't experience the same level of dampness as the PNW.

Ok, thanks for that info. Think I'll scratch that idea. I have used the boat on the water with air temps as cold as 32 degrees. (That's usually at night while sleeping in the V-Berth. Coldest day time temps are usually no less than in the low 60's. However, boatercamping on the trailer, I've slept on the boat with outside air temps as cold as 18 degrees. The Webasto does a great job keeping the inside of the boat reasonably warm. Condensation is usually not much of a problem during the day, unless it's cool/cold and rainy. And then that's mostly a window issue. I've tried various things at night, and about the only thing that works sometimes, is leaving windows open an inch or so. However, that's not quite possible during rain. I've tried leaving the front center window and berth hatch open slightly, but with enough breeze, rain still comes in. I'd really like to try some of the ideas with the thin closed cell foam, or car interior material, but I also don't want to end up with a mess to clean up later if it doesn't work. Part of me says just continue to deal with it, using the shammy to dry things up in the morning. I know I'm not the only one with this problem. I do go thru the boat usually twice a year with some mold and mildew spray to remove any that might be hiding in crevices and behind cabin wiring. But the problem does get old! Colby

 

[Dora~Jean]

Regarding keeping the side windows cracked a bit at night, or even during a rainy day with a lot of people in the boat while running. I read on this site 10+ years ago about a plastic, rounded deflector that could be fitted on the leading edge of the slanted side window frames to allow the window to be open but deflecting the rain. Something similar may have been available for older cars with wing windows.

So I looked up "deflector" and did a search on this site, found that it was B~C that did a custom design and installed back in 2004. A picture is in his album, I will attempt to insert it here. He did it to deflect the spray while running, but I see it could also be extended a bit to handle rain. Anyone else tried this or found an off the shelf solution?

 

[ssobol]

I put in opening side ports in the berth trunk. At night we usually sleep with the berth hatch open a little. Open the hatch, turn the dogs to the closed position, lower the hatch. This leaves it open about a 1/2 inch. Unless it rains really hard, no water comes in. Sometimes we leave the center window open the same way.

Even though there is some dampness, I've not had any problems with mold/mildew on the inside of the boat. I do find mold/mildew in the nonskid tread on the outside which can take some work to remove about once a year.

I am going to try some foam padding/lining on the v-berth sidewalls. My wife complains of cold contact with the walls when sleeping in colder temperatures. We have spent nights on the boat where the temps were below freezing.

 

[AKMel]

I'm thinking better insulation on the hull will help keep the boat warmer, but some form of dehumidification is necessary to deal with the windows. The humidity capacity chart of cold air versus warm air was insightful. Thanks. 1) I purchased a peltier dehumidifier for cheap. 2) I was PM'd to enclose the anchor rode area and install a 4" computer fan. The PM said theirs draws humid air forward (especially while sleeping) and exhausts it out the weep hole and deck cover, and in turn draws some cooler less humid air into the cabin. I'll try those in combination and see if I need any further steps.

 

[ssobol]

Has anyone thought of putting a heated element on the windows like rear window defrosters on you car? I could see doing something like this on the front windows (not the center one).

https://www.frostfighter.com/clear-view ... -about.htm

Seems like these come in a lot of sizes. You'd have to put up with lines on the window which some people probably wouldn't like.

There is also this, but it needs 115vac:

http://www.seaclearllc.com/seaclear2fix_012.htm

And this which does not require power:

http://www.seaclearllc.com/seaclear2fix_017.htm

 

[Ordutch1975]

I installed the wallas 22gb which has two intakes one for fresh air and one for recirculate. You can have the both draw fresh air but that is not recommended. I slept in the boat at 30 degrees which built some moisture but after turning the wallas on within an hour or so the windows were mostly clear. That is the only time I tested it in that weather and it seemed to work ok. I think pulling air in from outside does help create positive airflow to push moisture out. It’s not instant but seems to work.

 

[colbysmith]

Wish my Webasto would dry things out. It does a great job keeping the boat warm, all the way down to 18 degrees. I have tried using both outside air and inside air for it's combustion air, but notice no difference between the two. There are enough air leaks that I shouldn't need to keep any windows open. (Ie, sink drain and anchor rode hawser.) However, when I do crack a window or two, that does seem to help, except when high moisture outside such as rain. But once it gets below about 40, leaving the windows open is somewhat defeating the purpose of the heater. And without some kind of deflector on the windows/hatches, leaving them open during rain is not reasonable either... Colby

 

[Ordutch1975]

Mind you my boat is insulated on all surfaces other than the windows so that may help too...

 

[colbysmith]

Yes, I think that makes a difference. Two-Bears from your neck of the woods, has automotive interior in theirs and along with looking nice, they say it stays dry. I am very tempted to do something like that, but just not sure I should. I think it would be a mess then if I ended up having to take it out.

 

[Ordutch1975]

There are enough air leaks that I shouldn't need to keep any windows open. (Ie, sink drain and anchor rode hawser.) Colby

I am not sure about that - I slept with two friends on the boat in the fall before the heater install with the door and windows closed on my venture - come morning time I could not light my jetboil indoors. when I opened the door and windows it lit without issue. IE too little oxygen and dangerous.

The Wallas when not used for heat can be turned on to run as an air circulator. I am amazed how little power it uses with the adjustable fan speed. when it gets to temp it barely uses any current with the brushless fan running at low speed.

...

 

[thataway]

There are enough air leaks that I shouldn't need to keep any windows open. (Ie, sink drain and anchor rode hawser.) Colby

I am not sure about that - I slept with two friends on the boat in the fall before the heater install with the door and windows closed on my venture - come morning time I could not light my jetboil indoors. when I opened the door and windows it lit without issue. IE too little oxygen and dangerous.

The Wallas when not used for heat can be turned on to run as an air circulator. I am amazed how little power it uses with the adjustable fan speed. when it gets to temp it barely uses any current with the brushless fan running at low speed.

...

Two issues here: I find in most of the 22's there is a fairly good size opening under the cockpit combing into the cabin's aft bulkhead (both sides). This is probably bigger than the sink drain and perhaps the anchor locker; depending on the size of the deck pipe /or windlass line hole--both of these are probably going to be fairly high humidity areas.

I keep a SS scrub pad in this opening under the combings to keep critters out. There is always going to be some significant leakage around the doors.

Ordutch1975: I don't have any idea how well the new ventures are sealed--and I should have looked at the one which was brought to Hontoon by 3 Rivers Marine. But I would really be concerned if the presence of two people reduced the PO2 to a level where it would not support combustion by a JetBoil--A pulse oximeter is less than $20 at CVS or similar pharmacies, and would be worth carrying to roughly check people's oxygen levels. (another option is a single gas analyzer, at $130., if concerned) My experience with similar stoves when backpacking (in a closed boat there are certainly more dangers), is that they work fine at high altitudes where the ambient Oxygen is about 60% of at sea level. (combustion efficiency depends on both gas mixture and temperature at high altitudes, so that has to be taken into consideration.)

 

[Ordutch1975]

I agree as to the concern - I will never sleep in it without some sort of window or something open. It was 3 people including me. For the record I have nothing that would burn CO2 in the cab either. Well now I have the wallas but it exhausts starboard side. All fuel for my jetboil, and stove was kept outside.

The rear door and front anchor locker are sealed with rubber gaskets, windows seems airtight. So the only air exchange would have been through the sink which is likely not much as it has no where to go.

as to this "I find in most of the 22's there is a fairly good size opening under the cockpit combing into the cabin's aft bulkhead (both sides" I don't see any opening on my boat other than the slight opening to the cab for the control cables but that is in a tube and seems pretty well sealed on the rear where it exits the bulkhead.