Dehumidifier or Oil Radiator for 25ft boat?

[Richard.C]

I use a DD8L Junior on my 43ft boat, it stays on the boat all year round, comes in handy at beginning and end of season to prevent too much condensation on windows and hatches in the morning to clean up.

I don't know why you would want one on a timer, they are designed to maintain a preset humidity which is what you want it to do so switch it on and let it do it's thing.

 

[nicho]

Dehumidifier all day every day. They heat and remove moisture. Turn on, set the moisture level required, run the hose into the sink and leave.

I set ours to 50% humidity on auto and it keeps everything dry. Some set at 65%, I guess it’s trial and error.

 

[TonyR123]

+1 for DD8L junior. It only switches on when it needs to. Three settings for dehumidy (I have middle one). Highest one is to dry clothes I think. So far on a 4 month old sailing boat it is doing fine - no condensation in the boat at all. Drains into the sink. Although during the very cold spell not sure if the hose froze at some point as when I went to the boat the container was full. Could have been I didnt push the hose fully on.

Also have a 120w electric heater just in case.

 

[PeterBoater]

when I went to the boat the container was full. Could have been I didnt push the hose fully on.

Have you made a permanently open small hole in the top of the hose as it comes out of the spigot, as per the manual?

Reference somebody else's post, a desiccant dehumidifier should never be on a time switch, as it needs to go through a shutdown cycle for which it needs power on. Similarly, it should not be turned off at the socket without turning it off on its own panel first and allowing the shutdown cycle before turning it off at the socket. If it has a humistat, as the Meaco does, why put it on a time switch at all?

 

[TonyR123]

Have you made a permanently open small hole in the top of the hose as it comes out of the spigot, as per the manual?

Just re-read the instructions (as I usually skim read) and this was mentioned under "troubleshooting" - which obv I didnt read to begin with.

 

[Pleinmont]

Thanks for all your answers and feedback

 

[stone beach]

+1 for using a DH, a heater won't help, unless it is a very large one ! (joke)
+1 for leaving it on all the time to cycle on and off per the setting you choose, but i.m.o. don't set it too low IF you have a lot of woodwork inside. I experienced some splitting once which I put down to over drying during long winter shut down when the boat had been left to its own devices as I was far overseas. I find the mid setting is good on present unit (Meaco DD8).
As Chromedome explains very well there are 2 basic types, I've had them both, condensation type costs less to run but will not help if your boat is stored in cold ambient temps, like in UK winter, dessicant type is unaffected by low ambient temperature.... However a condensation unit will work as soon as the air warms up above about 5 degrees so you probably will not actually be able to tell the difference.
Currently I have one of each type, dessicant on the boat and condensate in the house to dry laundry.

 

[mil1194]

+1 for using a DH, a heater won't help, unless it is a very large one ! (joke)
+1 for leaving it on all the time to cycle on and off per the setting you choose, but i.m.o. don't set it too low IF you have a lot of woodwork inside. I experienced some splitting once which I put down to over drying during long winter shut down when the boat had been left to its own devices as I was far overseas. I find the mid setting is good on present unit (Meaco DD8).
As Chromedome explains very well there are 2 basic types, I've had them both, condensation type costs less to run but will not help if your boat is stored in cold ambient temps, like in UK winter, dessicant type is unaffected by low ambient temperature.... However a condensation unit will work as soon as the air warms up above about 5 degrees so you probably will not actually be able to tell the difference.
Currently I have one of each type, dessicant on the boat and condensate in the house to dry laundry.

I’ve set my DD8L Zambezi to 65% and it’s kept it as well as could be expected - everything is dry and mould free - including clothes and stuff hanging in wardrobes (doors left open!).

 

[Momac]

, dessicant type is unaffected by low ambient temperature...

Not so . The meaco dd8L does not work below 1 degree C ,but nor does any other dehumidifier.

I find the 'one drop' setting does the job = 60% rh.

 

[stone beach]

Not so . The meaco dd8L does not work below 1 degree C ,but nor does any other dehumidifier.
View attachment 148581
I find the 'one drop' setting does the job = 60% rh.
View attachment 148580

you are correct , I should have been more clear such as :- "dessicant type is unaffected by low ambient temperature down to 1 degree" .

 

[rbcoomer]

I'd say both. I leave a dehumidifier draining into the sink all winter and two 500w oil filled radiators on a low setting (around 5 degrees C) - one in cabin and one in engine bay. Boat is a Portofino 25 (open with heavy tonneau cover). Radiators to protect against frost not to keep dry, but maintaining a minimal temperature keeps the dehumidifier working. I also leave the cabin door ajar which minimises condensation inside the tonneau (tarp type, non breathable). One thing very noticeable is that on a sunny day, the dehumidifier removes far more water - the warmer air having higher humidity as more moisture evaporates. Working in the marina, I also have lunch on the boat often and will occasionally leave cabin radiator overnight on a higher setting which has the same effect as a sunny day (cabin door closed to retain any warmth).

 

[riverliver]

As much as the size of the boat matters, the insulation and "tightness" are to be factored in when trying to guess the need for capacity.

I'm not using my dehumidifier at the boat since October 2022 when I installed a bespoke full, breathable Fibertex cover. Now just leave the boat with windows and hatches open - and as always remove cushions and everything else, to keep indoors at home.

The cover is a different solution, just wanted to show you. Here loosely put on, before tightening the strapsView attachment 148518

I like that cover! Can I ask how much it cost? and boat length? Plus any problem using it with the boat on the water?

 

[ChromeDome]

I believe there are several suppliers - we have two nearby (Baltic), both so busy they don't travel far for work.
I'd suggest a search for boat winter cover breathable site:.uk

The covers are made to measure, so have to be visited twice - to measure and later to fit the cover. One of the suppliers will put a few pieces of tape on the boat, then send a drone up, fly around it and go home to feed the data into their system and then produce the thing.

Mine was made by the company below, who did the traditional measurement. The sewing is done in Lithuania, but the QA is done by the Danish owner. Tubes are cut to size on site.

Mine is 30' and could be made in one piece, some others (masts etc) are made differently, in sections zipped together.
I'll add a recent photo later today, the fit has improved now, helped by the weather & time (+ storms and whatnot).

Can be left on when in the water, but of course constant checking and re-tightening will be harder in the winter.

Slideshow and videos here FYI (Danish language)

Vinterpresenninger | Vintercover - GP Covers

I'm afraid I have no idea of the cost for your need - mine was about £3k including travel.

 

[ChromeDome]

Taken today in our marina. The first two pics are of my boat, the rest belongs to fellow boaters.

Not an uncommon cover solution..

Some are more on the spot with adjusting and regulating lines, as you see