Condensation on top of fridge cover

[Rorzech]

Originally Posted by nknowland

For the first time, I'm getting lots of condensation on the cover of my Alder Barbour fridge/freezer. Actually, from the end covering the freezer.

I have done all the basic stuff: replaced gaskets and insulation in the lid, the lid fits tight enough to pass the paper test, and I have an insulating cover inside, over the food.

I am in FL so understand that warm temps and humidity play a roll, but I am in FL and Bahamas every winter and condensation has never been this bad. Covering the top with a towel just leaves a very wet towel.

Any ideas???

Your condensation is just natural. If you want to stop it for good then you'll need to install a new door with at least 4" of closed cell foam inside it. But an easier way is to get some 2" thick SM construction foam and trim it to fit the inside top just below the door really snug like. You may need to poke a string through it tied to something (popsicle stick) on the other side so you have something to pull up on to get it out. You will be trading freezer space for luxury of not having to deal with condensation anymore.

[Sailmonkey]

We also do the bathmat on the counter trick when the humidity is high enough to cause condensation


Sent from my iPhone using Cruisers Sailing Forum

[Rorzech]

More air circulation drives the dew point temperature deeper into the lid until it goes past the vapour barrier then there is no more condensation outside the vapour barrier. Vapour barrier is always applied to the "warm"side of anything. A house its on the inside, a cooler it's on the outside. If you want your cooler to run longer then point a fan at it will run longer. if you want your cooler to run less. Apply closed cell foam insulation and seal it with anything from vinal Mac-Tac to stainless steel. Adding foam insulation assures your dew point will be buried deep enough to cause no condensing problems.

[Hard Rock Candy]

My refrigerator condensed water like a water maker. I finally discovered that the PO had insulated the whole freezer with Polyester peanuts. Polyester is nowhere near as good as urethane foam. The numbers I heard was like urethane is 7 times better insulation than polyester. Just a maybe. Mac

[colemj]

Originally Posted by Painted Skies

Ours appears to be primarily the result of the Corian countertops (which has to be one of the stupidest materials ever used on boats

This is a high possibility depending on what your countertop is. If wood, then not so much, but something like Corian will gradually get cooler and hold that temperature. It doesn't take much in a humid environment to get condensation then.

We have Corian tops also, as well as 6" urethane foam beneath it. Our box is very efficient and we have no issues with freezing/cooling or excessive power usage.

However, when it is humid, we get a small amount of condensation on the top, and the Corian in this area is noticeably cooler.

The "problem" stems from the lid seals. While they are tight and good, the rubber gaskets are not highly efficient insulation (or we all would just insulate our entire boxes with 3/8" rubber foam). This means the edges of the lid are always a very slight amount cooler than the center of the lid.

With a hard surface like Corian, this sets up the thermal mass problem where the coolness is retained in the surface rather than quickly equalizing with the air temp - and condensation occurs.

If your tops are wooden or similar, you should not have this situation (outside of unusually damp conditions where condensation is immediate on everything).

However, it if is hot and raining in Miami like another poster said, then I'm surprised your reefer top is the only thing on the boat covered in condensation.

Mark

[Terra Nova]

Sounds like a very poorly insulated box and lid with no vapor barrier.

[nknowland]

Thanks. We have a beautiful teak cover on our frig so haven't wanted to cover it completely! But this sounds like a good option.

[nknowland]

Thanks! I will try the peanut idea. Ice build up is worse over freezer, but it's already covered with a closed-foam pad.

[Typhoon]

I know this is an old thread , I just stumbled across it . You also must consider the thermal bridging of the material that is essentially, your door . If you are re-insulating you want to keep those edges as thin as possible , less wood and more insulation . Try to make the door fit the hole as tight as possible . I actually had to sand them to fit . Then use the paper pull test to make sure they are not binding and failing to seal on the lip, or getting hung up on the edges.

I know most of you have seen this video , but spring is coming and our minds will be thinking cold drinks so I will post it again .

Before I did these doors , I had the same problem. Wet counters. It was a little bit of work but now, no condensation at all even on the hottest days, also dropped my amp hour use down by 10%.

https://www.youtube.com/watch?v=F8SAku1HjXY&t=2s

Regards John