DEFROST ?

[Byrdman]

OK, looking thru this site in hopes of finding a solution to warm cabin, cold outside, and the need for defrost. Have seen leaving the windows cracked and yes that for sure helps... Saw on LYNN MARIE photo album, page 4, bottom left corner picture a "hair dryer" looking rig mounted to the ceiling....??? Any ideas or is this a system that does work and is available? Thanks! Byrdman

[MOOSE]

What do you mean by cold?
Al
International Falls, MN

[Aiviq]

Do you mean defrost, or defog? For frost, you need a window scraper to go out and scrape the frost off of the window, and perhaps heat to keep it from reaccumulating. For fogged windows (much more common), just moving air over the inside of the window usually does the trick. I have a 12 volt fan mounted on the ceiling that will blow on the window, and that defogs my windscreen very well. Heat (perhaps like the hair dryer thing on Lynn Marie) would probably work quicker, and you might need that for frost, but it would be more complicated and would use a lot more current. for defog, the plain fan works fine, will be cheaper and easier to install, and is fairly economical on your battery power.
Aiviq

[Lynn Marie]

Byrdman,

I'm the proud? owner of the hair dryer rig on the Lynn Marie. It helps, it all helps, but this is not a one system does it all kind of fixture. It only provides a minimal of heat and the fan doesn't really move a lot of air. I also have a small rubber bladed portable fan and that aimed at the window with the Wallas on takes care of things when it's fairly cold out and we've been in and out wearing a lot of wet rain gear or the boats been left idle at the dock for some time and things are cold and damp. With the Wallas warming and the fan moving air it actually clears up everything after a short time.

The other piece of equipment I installed is a solar/battery back up roof fan. It's a 4" model and I put it right over the Wallas outboard of the cabin top handrail. It keeps air moving and the dampness down even when we're not on the boat and also works like a range hood when the pots are steaming on the stove. The reason it works as a hood is that I have a small rack on the ceiling forward of the Wallas and another board that hangs down and runs from the rack back to the rear bulkhead. Like I said, it all helps.

Tim

[drjohn71a]

Hi guys... re: defrosting, there are several models of 12 V heater/fans that work well in small areas for defrosting. I have used several at a time on my old houseboat and even my motorhome. THey cost about 20-30 dollars and are readily available at truck stops and auto parts stores in cold areas. THey plug into the lighter socket. Note that they will only defrost a small area, but at least it is enough to see in a pinch. Opening windows does also help.

Byrdman - I have been anxiously awaiting photos of your macerater pump fix procedure......

John

[MOOSE]

Guest makes a really nice permanent-mount oscillating fan that I mounted last year on the underside of the electronics shelf. It works really well. It's not in the WM catalog; I got it from www.Go2marine.com .
Al

[Byrdman]

Yep, looks as if we are all on the same track...just keep more "dry air" moving. I have learned to keep the two adjustable fans running and blowing on the windshield when docking for dinner and I know the moister will build up... they seem to maintain OK, but bad news on catching up. Might also look at mounting one or similar fan over the aft seat of the dinette that could be pointed forward to help better circulate the Wallas heat a bit, and would also just keep the air (hopefully dry) rotating around a bit. Interesting on the "4 inch roof vent.." I have been playing around with hanging a fan from the ceiling hand rails and have it blowing out the aft window when cooking...

Dr. John: I was making the marine head much more complicated than it was... Not sure why I expected a hole to be in the floor other than that is where it goes in the house... I was glad I had that one gallon wet/dry vaccume once I did unhook a couple of hoses. Nothing worth taking a picture of other than my uninformed face. It was sort of like an Easter Egg hunt...and thankfully, no "eggs" were found.

[SENSEI]

I have been looking at this little ceramic heater fan for defoging the front windows.

has anyone had any success with these they are item #389298 in the West Marine catalog online

[rogerbum]

[Sea Wolf]

Roger & Roger-

I've had a similar model with similar results. 8.3 amps x 12 volts = 100 watts. Nice, and in easy conditions, it will keep a single window marginally clear in situations where the moisture in the boat air is not too challenging and the outside temperature is not really terribly cold. But it's not a cure-all for the defogging problem. Has just as much heat to offer as a 100 watt light bulb, since most of the 100 watts in an incandescent bulb actually is radiated as heat, not light.

Realistically, though, the problem of defogging can be anything from a minor annoyance easily blown away with a small fan to conditions that could defeat even your car's defrosters even after the engine is fully warmed up. Moisture comes from breathing, perspiration, unvented heaters/cooking stoves, wet clothes, foul weather gear, and dogs. I've found that I can deal with most of the above, sans as case of really wet clothes, wet foul weather gear from trying to troll in the rain, and of course, my 175 lb Great Dane, Shadow, when she's a wet, stinking mess!

The steps involved in defogging will vary somewhat based on the situation, but usually include the following:

Turn on ventilating fans on the windows- I have two mounted ones that can oscillate, and a similar third one mounted to a Stanley metal giant clothes pin style spring clamp with a cigarette lighter plug that can be moved around the boat as needed. These are the most efficient defogging units of the various devices used.

Provide ventilation to external air to get rid of the excess humidity. A vent, cracked window, etc.

Turn on your Wallas, Force 10, Dickinson, Toyomi, Webasto, Espar, or whatever to raise the temperature in the cabin and thus lower the relative humidity. This does not apply to unvented heaters, e.g., propane heaters w/o external venting, as they will simply add to the water vapor problem.
The Origo alcohol stove (original equiment) on the C-Dory is a very bad water vapor producer and a problem itself when used in cold weather.

Use another fan like the ones in the front windows to circulate air throughout the cabin, thus spreading the water vapor around evenly, distributing the heaters warmth, and assisting in getting fresh air into and out of the cabin. An exhaust fan would be useful here.

Turn on your small defogging windshield heater directed at the helmsman's starboard front window.

I've not done this, but in extreme climates, one could install a tube from the heater output area over to the front windows powered by a couple of computer CPU fans, one at the intake and another at the output, placed at the bottom of and directed upward on the window directly in front of the helmsman. Probably could be done with clamps like the one mentioned above and the same type lighter plug so it could be removed when not being used, as space near the cabin top is at a premium in our boats. The Toyomi, Webasto, and Espar units are really forced air diesel furnaces and have their output directed in tubes, so this would be a natural for them.

The real task here is to figure out how to get as much hot dry air as possible to the windows as well as the cabin with what we've got to work with. With an inboard engine, you could use hot water from the cooling system to get the job done with a cabin heating unit and ducting.

If you've got really wet clothes, gear, or whatever, change it out and put it in a plastic garbage bag to be dried out later, rather than let it fog up the windshield for the next hour or so.

If you have to go out in the rain to tend the rods, put up the bimini to minimize the pick up of rain on your clothes.

Stop trolling, anchor, and still fish if it means you don't have to go out in the rain as often.

Go back to your covered berth and fish under a roof. In my case, at least, there are more fish (bass especially) concentrated under the marina than in most places in the lake!! Since you're not driving right now, turn on the coking stove, heat up some water, and make a couple of Irish Coffees and contemplate how good life is with the C-Dory!!! AND Think about how to devise a better defogging system! Hmmmmmmmmmmmmmm???!!! Joe.

[Sneaks]

Jeeze, back in the old "Monument Drive In" days (Da Nag remembers that place, I'm sure) on dates I'd often get the inside windows of my '48 Chevy all steamed up for reasons I won't go into at this time.

Try swiping a bar of Ivory soap across the windows a few times when the window is dry and rub it out with a hand towel. It ain't permanent but it does last quite a while.

[Da Nag]

[Byrdman]

Good Stuff Guys.... Got me thinking of the inside cabin layout on the TomCat, one of those larger Turbo Blowers with the intake side somewhere in the port/aft cabin corner (as to not hit the head of someone facing forward in the aft dinette seat), with some type of "flat wide" duct work that could be temporarily "slung" and run mid ship against the ceiling and between (inside with room to grab the rails) the grab rails, then forked between the port and starboard window. The dry warm air is in the boat and with the lid down and wallas blower blowing, forced from the aft starboard toward the aft port, and rises as heat does, especially if pulled toward the roof by the turbo fan.. OK... that is a general concept, ...... anyone seen any 2"x6" square pvc duct work of something light weight/cheep....? Byrdman