Ice Box insulation on a CD 31

[jen1722terry]

Hello Fellow Members!

Jenn and I are the happy new owners of a 1984 CD 31 with the original ice box. We'd like to add insulation in anticipation of either adding refrigeration, or installing an ice machine to make ice as needed. Some of our cruising grounds (Nova Scotia) do not have a lot of marinas that sell ice.

If any of you 31 (or possibly 33) owners have insulated their ice boxes, we'd sure like to hear the details, particularly what materials were used.

And thanks to all of you for your kind posts to our other questions

Jennifer and Terry McAdams
Kearsarge, NH
Mahone Bay, Nova Scotia
jen1722terry@gmail.com

[Squid]

Jennifer and Terry,
I wanted to respond to ensure I track the discussion you may create. I have a 30 MKII and have gone through all the mental gymnastics of how to or if to modify. My thoughts, worth what you paid for them and for my particular boat only.... I am not sure going through the potential electrical upgrades is worth the effort. You may have different requirements, understand. I have added A/C and talked with the guy who runs the company about all the potential refer install considerations, new larger alternator, smart charging upgrade, larger batteries, wiring upgrades and in the end not all that efficient unless you are on AC. While on DC or battery, there is still some loss of efficiency with a large pull on the battery bank. My thoughts for this winter project is to pull the side panel next to the ice box out (between ice box and oven).... install as much insulation as possible, and then patch the wall back in place with teak trim. Hopefully next summer will yield me a better ice holding capability which is pretty bad right now. Again, just my thoughts but am eagerly waiting to see what responses you may get.

Glen

[paulk]

I was considering this init (Isotherm Compact 2010 Refrigeration System) from Defender to upgrade my CD27 icebox. Will appreciate any comments. It's air cooled and will run from 12V.

[Steve Laume]

No matter what you decide to do, insulation is the first step. On Raven I still use ice but an able to go at least five days. I hole sawed a grid of holes from inside the box all the way around and especially the bottom. Exterior low expansion foam, then epoxy the plugs back in, fair and paint.

There are a couple of threads on here where I know I went into a lot of detail about doing this, Steve.

[Squid]

Steve,
Your method was the other thought I had, to whole through from the ice box side into the void and fill. Then fill in with thickened epoxy when complete. The other method I was considering was pulling the oven (I have a different interior deck/galley plan U-shaped). RIght now in the height of summer one block and three bags of ice last 1.5 days, pretty bad. And I keep the beer and soda in a different cooler in the head. From my little bit of research, five days is what should be expected, so it seems you have hit the mark. My thoughts are once the oven is out, pull the majority of the bulkhead out from the side of the ice box, reach to each side, back and bottom with slow rise foam and then epoxy back in the bulk head and cover the cut with half round teak trim... any thoughts before I cut or drill??

Thanks,

[Steve Laume]

Unless you are going to completely rebuild your ice box I would not start tearing the cabinetry apart.

I think I did a 6" grid and started filling from the bottom. Go slow and fill until you reach the next set of holes. Using a hole saw to drill the holes and save all of the pugs. These will make filling in the holes much easier. I epoxied them all back in without any cloth and then faired them for paint. It has been a few years since I completed this project and there is no evidence of the liner being plugged.

What you will find when you cut the first hole is that there is about an inch of insulation and then another thin layer of glass. Drill right through both layers and foam fill all the way to the hull or bulkheads. I did saw out a small access area on the inside of the forward bulkhead, which is inside of a cabinet on the CD-30. This allowed me to slide a shield into the bottom of the ice box area at it's lowest point, where wires are run. You don't want to cement all the wiring in place in case you ever have to change anything.

I removed the deck fill for my water tanks a few years back. I always fill through the inspection ports at the top of the water tanks. There are lots of good reasons for doing it that way. The point I wanted to make is that I cut out all the fill line except the section that went through the ice box area. I left this in place as a wire way in case I did have to send some more wires through there and my efforts to block the foam were not completely successful. You could add a piece of pipe for future wire runs if you are keeping your water fill line.

There are some areas where there just isn't much room for insulation. The most troubling is the bulkhead that separates the ice box from the, hot, engine compartment. I did add sound insulation to the engine compartment which also adds some thermo insulation.

Keeping the box cold also requires some management. Freeze anything you are bringing from home that can stand it. I also start from home with frozen milk jugs full of water. This can be consumed once it has melted. When I need to buy ice, I try to get blocks and whatever ice I do buy goes into a dry bag so the water cannot escape. Not having melt water in the ice box allows me to keep a closed cell foam plug in the drain so no cold air can escape. I also keep a stadium blanket on top of all of the food so I need to cool less space. Things that you might want to get at frequently and do not have to be very cold can go on top of the blanket. For me this would include a 2 liter bottle of diet Coke. If I want some, I just reach in and grab it off the top without disturbing any of the other contents. The IPA goes in the very bottom, snuggled in between ice jugs.

Refrigeration would be nice but I have a list of other stuff that I would purchase or replace that comes way before another major energy consumer and possible source of problems, Steve.

[Phil Shedd]

Jen and Terry

I have installed a isotherm unit on my boat. I will keep the icebox around 4-6 degrees C. I feel the unit runs about 15 to 20 min an hour depending how hot it is out and how often you are getting beer. Since I am at a slip and have power I can leave it turned on all the time and fully stocked.

When I first installed the unit I found it was running a lot so figured I need more insulation. I looked at various things foam, ridged sm board , rebuilding the whole thing( big job). However what I ended up with is ( are you ready) concrete foundation insulation. This is like foil with bubble wrap between the two layers of foil. I cut it to shape and used contact cement to install it . It may not look all that nice but it can be cleaned and helped a lot with keeping thing cool.

I usually go down to the Maine coast for a couple weeks each summer and have not had any mayor battery issues running the unit.

Hope this helps

Phil

[M. R. Bober]

The best advice that I got when I started STARVIEW's conversion from icebox to reefer was to reduce the size of the Cape Dory icebox. They are huge, designed to hold lots of food and LOTS of ice. The second best advice was to use factory made insulation panels rather than injected foam. The factory made panels are void free.

Cape Dory used a box inside of a box, with 2" of foam panel between the boxes. I verified this by drilling several examination holes through the inner box. I decided on a size, built a bit of framework, installed another 2" of rigid insulation (foil faced on both sides) with construction adhesive on all sides and the bottom, then lined the entire box with vinyl sheet (the stuff that hardware stores sell for tub surrounds pebbled on one side smooth on the other), and then caulked all seams.

Too big a box and your compressor will run and run and run, and you might need to upgrade your house battery bank. I used a Frigoboat compressor with a hull mounted heat exchanger.

Decide how much freezer space you want, in any.

Let us know what you do, and good luck.

Mitchell Bober
Sunny Lancaster, (Where I can raise water to the third power.) VA