Dehumidifier

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here is our setup -

Dehumidifier from Lowe's on a timer to run for couple hours each day while we are gone. The hose drains to the galley sink. I keep a digital temp and humidity gauge on the lower helm that records the max ratings while we are gone and tends to stay below 65%. Picked the location based on easiest way to drain.
 

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I'll bump this thread. We had more "Pineapple Expresses" go through the PNW last year than I can ever remember. The "Dries Air" chemical anti-desiccants were overtaxed. I just purchased a Garrison dehumidifier: 28 pint (13 litre) 298 watts (3.2 amps). I have it running at home in the basement right now and it removed 1 litre in about an hour. I intend to set it on the Galley counter and run a hose into the sink (through hull above the water line). Another option is to set it in the companion way between the staterooms and have the hose run into the sink in the amidships head.

We just got back from a trip with guests and found that the bottom bunk in the guest state room was quite wet under the mattress. I intend to get some of that Hypervent mesh to put under the mattress. Expensive stuff at $14Cdn a linear foot!

Jim


Which is why I throw this on top of the spare bunk before throwing down the mattress: True Blue 20 in. x 30 in. x 1 in. Budget Washable Filter-0120301.1 - The Home Depot

cheap and works fine.. if in doubt, use 2 layers, it is still cheaper. Under the main mattress (live aboard) we use curved bed slats from Ikea with a mattress cover (cover is kind of plastic like, but you get used to it)
 
Which is why I throw this on top of the spare bunk before throwing down the mattress: True Blue 20 in. x 30 in. x 1 in. Budget Washable Filter-0120301.1 - The Home Depot

cheap and works fine.. if in doubt, use 2 layers, it is still cheaper. Under the main mattress (live aboard) we use curved bed slats from Ikea with a mattress cover (cover is kind of plastic like, but you get used to it)


Yes...well...I sprung for the Hypervent. Furnace filters could have been a workable alternative. I thought it was going to be the same stuff that the PO put under the mattress in the master stateroom, but, it's not as thick. I needed 7' of the Hypervent. It's 39" wide.

Update. I got the dehumidifier going in the galley. The humidity dropped from 88% down to 56%. I'm going to temporarily set it up in one state room at a time and then the Pilothouse, before I leave it full time in the galley. That way it will remove all that moisture pent up over the summer.


Jim
Sent from my iPad using Trawler Forum
 
How about the engine room. Do you use a dehumidifier in that area? How do you dispose of the water collected. If you leave a hatch open from the engine room to the salon will the dehumidifier work down there? Thanks guys...
 
To be effective, you'd have to close off the ER vents, otherwise you will be attempting to dehumidify the state of Louisiana.
 
To be effective, you'd have to close off the ER vents, otherwise you will be attempting to dehumidify the state of Louisiana.

Makes sense!

I remember from last winter the condensation all over the engines and other systems. Need to rid that area of all that moisture. I can't go with heaters...scares the b jesus out of me to leave electric heaters on in the bilge area.
 
I use an Extreme heater in my engine compartment. It does help keep condensation down in the winter. It is designed for use in an engine compartment, so I don't worry too much about it. There are other boat safe heaters out there, that work just as well.

I don't think electric dehumidifiers work very well in temperatures below 50F.
 
Makes sense!

I remember from last winter the condensation all over the engines and other systems. Need to rid that area of all that moisture. I can't go with heaters...scares the b jesus out of me to leave electric heaters on in the bilge area.

Think about block heaters. The ones on my Detroits could keep the whole lower level of the boat dry as well as warm.
 
Think about block heaters. The ones on my Detroits could keep the whole lower level of the boat dry as well as warm.


Yes, I've thought about a block heater, but I understand they use a fair bit of power. I've only got 20 amp power right now, so don't want to be tripping breakers when I'm away.


Jim
Sent from my iPad using Trawler Forum
 
We have used dehumifiers on our boats for a long time. We are in a slip with shore power so it is easy. Keep the interior of the boat dry. They have a strong fan so if you put it in the main saloon or galley it will circulate air pretty well. We also have two of those circular Air-Dry fans that we keep in the forward and aft cabins for more circulation and just a very small amount of heat. It works great, keep the interior of the boat extremely dry.

Again, the interior volume of my 40' boat is a lot smaller than most of yours, but it should work well.
 
Heating the ER can drop the relative humidity, but if you're not comfortable with ER heaters, a fan to keep the air moving will help in reducing the condensation.

We use an electric oil-filled radiator style heater on a timer. It cycles ON/OFF to keep the ER temp in the 60 degree range. No exposed heating elements, no fans, no noise.

space-heaters-01.jpg
 
We have used a heater similar to Fly Wright. Works well but when we store at a marina in a cover slip, they will not permit a heater. We've also used an Eva-Dri dehumidifier which works well, until the temp drops below freezing. A fan does circulate the air in the saloon, it doesn't freeze.
 
Santa brought me an Eva-Dri EDV-2200 for the boat. Will be adding a drain hose before taking it to the boat. Thanks for the great suggestions here. No more Dri-Z-Air calcium chloride pots for me!!
 
You'll like it Al. I used a piece of aquarium air hose for the drain on mine. I just drilled a hole in the tank a little smaller than the OD of the hose, shoved the hose in and it's worked well ever since. No sealant or fittings needed.
 
Thanks, HC! I bought a valve with the intent to tap a hole and thread it in but after bringing it home, it seemed more complicated than needed. I like your idea of a simple, snug fit. I have 1/4 in OD hose. If I need to plug it, a 1/4 in plug would be a simple solution.
 
Many marinas now have electric meters , and monthly bills for service.

Those that do not soon will as electric costs are being driven up 300% by edict.

A solar vent or good natural venting might save $3,00 - $10.00 a day .
 
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Many marinas now have electric meters , and monthly bills for service.

Those that do not soon will as electric costs are being driven up 300% by edict.

A solar vent or good natural venting might save $3,00 - $10.00 a day .

What's nice about the Eva-Dry 2200 is it's low power consumption. It has a 120 ac to 12 vdc power adapter and draws 6 amps at 12 vdc.
 
Any reason why the Eva-Dri-2200 was selected rather than the smaller 500--can get a package of 5 of them and spread them around.

I don't see a lot of (any) technical info but says no wires, cords or batteries. Assume this is a container of some sort of crystals and the 2200 requires a power source.

https://www.eva-dry.com/special-offers/
 
Ktdtx, I tried using the chemical moisture absorbers and found they need to be emptied often and the chemical replaced. The little electric dehumidifiers, with a drain installed, can be ignored for months and they just keep working.
They don't last forever. I've had the fan go bad on one and the hot/cold thing go bad on another. I still like them much better than the chemical absorbers.
 
I've have used one just like it for at least 15 years and it is a great reliable refrigeration machine! Unfortunately, they are no longer manufactured...
 
I just bought a GE 30pint/day unit for my boat from Lowes. I've been living on my boat while I am building a new house and the winter conditions make for a humidity disaster. This little unit really works well and is quiet. In the summer, humidity is not a problem due to AC's being on. In the winter boat is kept closed up and heat does not remove moisture. Sometimes I would have to open up the boat in the cold just to get an air exchange.

Now after a shower just hang up the towel in the boat. In the morning it is DRY!!!

I'm so happy.
 
Do you drain that to the sink or somewhere?

My boat is feeling really humid lately also. I have a little Eva Dry draining to the sink but it's not keeping up I guess.
 
Do you drain that to the sink or somewhere?

My boat is feeling really humid lately also. I have a little Eva Dry draining to the sink but it's not keeping up I guess.


I have two of the small Eva Dry. One in the galley which gets the salon and one in the head which gets the head & V berth.
They both use a short length of hose to drain into the sinks.

If your boat is still too humid then one may simply not be enough.

You likely also need some fans to force circulation of the humid air past the Evas.

They do work but if the boat is larger than mine, 32, and the air is high humidity then one small one may simply not be enough. I also use a myriad of fans to force air circulation. Otherwise high humidity areas will remain as I've seen.

One large dehumidifier may work as well BUT WILL need some fans to force circulation so moister areas can be cleared.
 
I have two of the small Eva Dry. One in the galley which gets the salon and one in the head which gets the head & V berth.

They both use a short length of hose to drain into the sinks.



If your boat is still too humid then one may simply not be enough.



You likely also need some fans to force circulation of the humid air past the Evas.



They do work but if the boat is larger than mine, 32, and the air is high humidity then one small one may simply not be enough. I also use a myriad of fans to force air circulation. Otherwise high humidity areas will remain as I've seen.



One large dehumidifier may work as well BUT WILL need some fans to force circulation so moister areas can be cleared.


Mine is 41' but not lots of interior space, but I think I still might add another one in the head and drain it into the sink.

What kind of fan do you use to circulate the air?
 
Using a dehumidifier

A couple of things.
1) I have a water in my bilge
2) I have a full custom cover that covers my boat. It is dark blue, so even in
January when it is 0 degrees centigrade outside, as long as it is sunny it can be 13 degrees centigrade under the cover on the boat. Inside the cabin it can be 6 degrees centigrade.
Of course, when the sun goes down, and it is 0 degrees centigrade or colder, it will be freezing outside the boat under the cover and inside the boat.
3) I have 3 Camfro air circulating units
4) I presently don't have a humidifier

Question.
Will water in the bilge negate the benefits of having a humidifier? Should I tighten up my stuffing box in the winter to prevent any water from entering the bilge when I use a humidifier?
If I leave the windows open, would the effect of the hot temperature on deck under the cover essentially dry out the boat and have the same effect as an humidifier.

If I got a humidifier during the winter layup period would be of any benefit?
 
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I use small muffin fans. The case size is 90mm. They each draw about 10 watts at 120V. I buy them from Newark Electronics by internet. Almost all are ball bearing, not the sleeve bearing units. I do have some sleeve type but they have given me trouble.
I place several of them around the boat. Actually the last time I counted there were 17 total.
4 in the salon, 4 in the v berth, each set up to force a circular travel of the air.
2 in the head, one pointing in and the other out the propped open door.
The flow is arranged so that circulation goes past the Evas.
1 blows out of the V berth. 2 in the engine compartment, 2 in the lazarette all again circulating the air.
1 pulls air out of the bilge area in the v berth as it is quite enclosed and gets water into it from the chain locker.
This way the odds of localized stagnant, high humidity air is minimized..
2 are mounted in the salon windows, one port, one stbd., so they blow OUTWARDs.

It took me more than one winter to set this all up as some of the fans and placements were reactions to specific problems due to humidity.

The EVAs are on a timer set to run twice daily for ~ 3 hours each time. Not much point at night as they can freeze.

I also use several low wattage heaters each on a T.stat so they only come on when the temp. heads for freezing.

My boat is also under a full custom cover/tent which was made for it so although some rainwater gets in, the boat is protected. Just not perfectly.

Part of the reason for all the fans is when we came home from our winter travels there was a faint dampness odour, sometimes stronger than I liked. I was not happy. With all the fans that odour is gone.

A wet bilge will not help as that water is a source of constant vapour. Either adjust the stuffing box to cut water way down or figure out a way to keep the level way down. I don't recommend cranking on the stuffing box as the next spring at recommissioning time loosening the nuts will NOT loosen the packing and then may be too tight. Just adjust so the absolute, acceptable minimum drips through.

I'm home this year, no travel, but normally what I have done above takes care of things for me. Of course the boat is fully winterized on top of my fancination. I just don't want that odour or the resulting mildew spots.

If you are able to monitor the boat frequently during the winter then a lot of this may not be required. Before we started travelling I would go and open the boat two or three times weekly and work in the cold, letting the breeze blow through. Cannot do that and don't like that so much anymore.

As for the question about the dehumidifiers, YES, they will help but they cannot fix a leakage problem. Reduce humidity driven damage, yes, but not fix it if there is a lot of water entering.

I know quite a few folk who use them, larger than mine, and now swear by them. Odour gone or reduced and mildew reduced/gone.

Sorry for the tome.
 
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What's nice about the Eva-Dry 2200 is it's low power consumption. It has a 120 ac to 12 vdc power adapter and draws 6 amps at 12 vdc.
I selected the Eva-Dry 2200 because it operates on 110v North American, 220v European and both 50/60 hertz. Hard to find a dehumidifier that accepts the different power supplies of boat yards in various parts of the world.
 
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