condensation in boat

[fredflathead]

Went out hairtail fishing in my new second-hand boat, this boat replaced my old crest cutter of 30yrs. The new boat has clears all around and can seal the weather out really well however I found condensation forming the in the cabin. 

Any ideas about stopping this, I think I will have to let in some air to compensate for the temperature inside and out.

 

thanks Norm

[frankS]

You can buy a small 12 volt heater to put in the cabin which will just take the chill out of the air and stop the condensation.

Frank 

[xerotao]

43 minutes ago, frankS said:

You can buy a small 12 volt heater to put in the cabin which will just take the chill out of the air and stop the condensation.

Frank 

Wont it make more condensation if warm air is inside cab and cold air is outside?

imthinking about ways to battle condensation for my next hairtail outing

[frankS]

I guess it's the small fan than circulates the air that stops the condensation.

Frank

[BaitDropper]

It's all down to air flow.

One suspects when you store the boat, she's all buttoned up and those clears will act as a glass house does, or the window sill of your house, with the winter heating on.

I don't have full side clears, and when I store the boat, with my covers on, she will get hot inside when I climb in to tinker with something, if it was a clear cover, I recon it sweats so much more. Condensation will soon turn to mold if left for any length of time, with the best fix, is to get air flow into the equation, especially when storing and not using.

 I'd be undoing the side and back clears, and drop a one piece cover over the top, that will allow a bit of air to flow, a full pull over cover. covering the whole boat, will stop light getting in there and help, plus it will protect and help the life of the canopy and clears to boot !.

[Marky mark]

I'm guessing this is while you are out fishing on a cold night? Oddly our breath contains a fair bit of moisture and over time this water vapour hits the cold surfaces and condenses. Increasing the airflow would definitely help but lets in the cold your trying to keep out! I'd go with some sort of heater/fan in the first instance, keep the air moving and warm so it can carry the water vapour better and not let it condense so much. Also maybe a couple of those moisture absorbing buckets from the big green store opened up in the cabin would help? 

[XD351]

Airflow will help or you could try treating the inside of the clears with something like rainex - this will help  the condensation to ball up and run off. 

[fredflathead]

The moisture was on the cabin roof, if I open the front hatch about 1"  Also, the rear clear rolled up about halfway It was when I woke up in the morning the sleeping bag was slightly damp and the roof of the cabin was wet my sleeping bag is  - 15 degrees so I will still be warm.

 

Thanks for the replies.

[riveRecon]

Air movement is the key I have found. I have a Bimini which gathers enough condensation under it it starts to “rain” with no clears or side walls. When references are made to ventilation, the actual meaning is air movement. I’m still experimenting with the ideal set up. If you can direct low speed fans to keep the air moving across surfaces, condensation will have a hard time forming. Warming up the air alone will make the condensation worse, humidity on the water is extremely high which keeps recharging the atmosphere with moisture. The water temp is normally warmer than the air, the water evaporates into cold air, which it then wants to condense on first surface it can find. That’s why fog forms over water and why any boat is completely soaked in the morning. Most adults also breathe out about 2 liters of water per night. You’ll notice if there is a continuous breeze, no condensation forms. Sorry for the long winded “pun intended 😀” reply. I hope that helps - air movement is the key.

[XD351]

The subject of condensation is something I had to delve into fairly deeply to sort out the condensation that was forming on my machinery in my shed , the important factor is the dew point which controlled by humidity level - high humidity = higher dew point temp . Once the surface of an object reaches or goes below the dew point condensation will form if the air in contact with that surface is warmer than it , the warmer the air is the more moisture it can hold and the greater the condensation will be . In my case I had to use covers and a dehumidifier under the cover to lower the humidity and thus lowering the dew point , this can’t be done in a boat so keeping the air inside at the same temperature as the surrounding surfaces and the humidity level the same as the air outside is really the only option . If there is no air circulation the heat from your body and breath will  warm the air under the canopy a small amount so it is warmer than the surface of the canopy and your breath adds moisture to the air lowering the dew point of the air under the canopy . 
Maybe a couple of these types of fans running in a push - pull configuration would do ?( one blowing air into the area and the other blowing it out the other end ) I was thinking a fan that oscillates will give more coverage .

[fredflathead]

Thanks for all the replies, I have a USB small desk fan. The boat has USB sockets so I will try the option.

[XD351]

Just make sure it is pushing in air from outside , also having air flow across a surface can cool it down - like wind chill  and make things worse so don’t point the fan directly at the surface that is causing the problem , you just want to exchange the air inside with air from outside to equalise the humidity and temperature. 
Another option which may work is to use an infrared heater to heat the offending surface but then we are getting into other problems like powering it .