Adler Barb Owners... want a freezer?

[Cruisingdad]

I have a stadard Adler Barbor refrgeration unit on my boat. I suspect most production boats (and many non production boats) have the same. The temperature is controlled by a analog knob, with 1 being warmest and 7 being coldest.

It has worked well as a refrigeration unit, but I always wanted a freezer too. The freezer space is really limited to the inside of the evaporator.

Now... want a freezer too but not install the extra equipment?? Here is how I did it and I bet it would work on many other boats.

I removed the evaporator (four screws) and placed it in the bottom of the refrigerated area (the box) and screwed it in there. I then went to Lowes and bought a $8 pack of styrofoam (it is with the insulation). I then double insulated the entire fridge and taped it with aluminum foil tape (HVAC tape, also at Lowes). I did NOT do the bottom of the fridge because water has to drain there.

I did this because most (if not all) fridges are highly under insulated. I then built a shelf to divide part of the evaporator - with 25% sticking above the shelf and the bottome third below. Now, on my fridge, I have a door. I sealed in (after the styrofoam) everything so that the bottom part could only be accessed by the door. I then cut out thick sheets of platic that hung in strips from the door opening, so that when you open the door, you will have to stick your hand through this plastic sheets to get to it. I also cut out a square piece of styrofoam to insulate (in addition to the door and plastic) the freezer area.

Cold air falls, hot air rises. Using that principle, the enclosed area you made at the bottom will become a freezer. The top part will become your fridge. You need a way (either by holes or fans or something) to increase or decrease the amount of cold air in the refrigerator section. Every boat/box is different so you will need to play with this some - but it should work well.

I also went to radio shack and bought two large CPU fans (about 2"X2"). They draw only milliamps. I put one high in the fridge and one in the freezer. These circulate the air in both.

I then set the temp dial to 6 (of a possible 7). I draw 54 amps/day (not all of it is refridgerator and freezer, but most) from about 46-48 amps day. My temperature in the refrigerated section is 36-38 degrees F. The freezer is in the upper teens to low 20's. Everything in the freezer is solidly frozen.

I will try and post pics of this next week. Forgot to take pics to show. But it is a simple and inexpensive way to have a freezer and fridge on your boat. The key is moving the evaporator to the lowest area and really insulating the box well. Do not use duct tape to tape up the seams, use the foil tape. It seems to be more moisture resistant and a better product.

Hope this helps some of you.

- CD

[sailingdog]

CD has got way too much free time on his hands...

[Lion35]

Nice job CD, thanks for writing it up. What's a BBQ good for without cold beer and ice? Most production boat boxes I've seen are under insulated, specially for the tropics (or Texas for that matter.) I'm hoping on revamping my old ice box (currenty only good for chemical storage) this winter and your experiences will go into the design.

On a simular note: I read an interesting post on the Peterson 44 list where a guy ran his water cooled Adler Barbor H2O intake and exaust to his fresh water tank. I thought this was a briliant idea. No chance of sinking the boat with the fridge and no salt water running through the heat exchanger. 100 gallon or so heat sink. I thought it would be great to add a filter to the system so you are always filtering you're fresh water at the same time.

[Wayne25]

So if I remember this formula correctly, #water x temp rise = BTU
500 BTU / (100 gal) (8.34#per gal)=.6 degrees per pass or per hour. I'm guessing at the BTU of the Frig. Either way he will have a hot water tank and make the refig go out on limit switch.

[Lion35]

Thanks Wayne, I don't have anywhere near your on knowledge of the physics, but I would love to understand this better.

Do I understand the sum of your calculations is the water in the tank would rise .6 degrees every hour the compressor ran? Obviously that is assuming the tank is full, which it won't be most of the time, and that the tank contents are cycled through the heat exchanger once an hour.

This doesn't seem too bad to me if the compressor only runs 3-4 hours a day, I realize 3-4 hours per day is an "if" and assumes a well insulated box. If the tank was on average half full (50 gallons) you would rise the water temp 1.2 degrees per hour or 3.6-4.8 degrees per day. wouldn't the tank cool back off enough in the idle time? Is it that a sealed tank with a small temp difference to ambient temp won't loose it's heat quickly?

I'm not being argumentative, I'm just trying to comprehend this better.

CD, this seems on topic to me but please let me know if you consider this a high jack of your thread and I'll create another one.

[Wayne25]

Yes, lots of variables, like does the water start out at 90* if your in southern waters or 50* if your in northern. I also have no idea of the BTU capacity of the frig. Obviously more BTU would heat up the water faster. Just wanted to point out that there is a limit to the 100 gal heat sink. That limit being the point at which the frig turns off on a temperature limit switch. And probably at the worst time possible.

[sailingdog]

Of course, using a freshwater tank as the heat sump for a refrigerator isn't the best idea in the world, since the heat capacity is related to the volume in the tank and the ambient temperature. In hotter climates, where the refrigerator would be working harder, you'd also have a less efficient heat sink, since the water in the tank is hotter to begin with, and that is compounded by the fact that you probably use more water in hotter climates... so as the need for increased heat sink capacity rises, the actual heat sink capacity will probably decrease.

[JohnRPollard]

CD,

Nice upgrade. Well done!!

Of course, it helps that you have a front loader, i.e. a swing open door on the fridge. That's not the most common arrangement -- ours is strictly top access. But maybe I could find some way to create a second "trap door" at the bottom of an upper fridge compartment. All I'm looking for is the ability to make ice cubes for soft drinks, first aid, etc...

P.S. Do you know whether the fridge arrangement on the Catalina 42 is similar to yours, i.e. does it not have a separate freezer compartment inside the ice box?

[recycle]

I'd love to see photos. Sounds interesting

[Cruisingdad]

Originally Posted by JohnRPollard

CD,

Nice upgrade. Well done!!

Of course, it helps that you have a front loader, i.e. a swing open door on the fridge. That's not the most common arrangement -- ours is strictly top access. But maybe I could find some way to create a second "trap door" at the bottom of an upper fridge compartment. All I'm looking for is the ability to make ice cubes for soft drinks, first aid, etc...

P.S. Do you know whether the fridge arrangement on the Catalina 42 is similar to yours, i.e. does it not have a separate freezer compartment inside the ice box?

Hi John,

I cannot remember if it is the same setup of not. I am pretty sure it has a front door. Regarding your setup, it really wouldnot be any different. The only exception is that you have to divide your box vertically instead of horizontally. It would actually be more efficient that way too.

The new Catalinas (on many models, like the 350 IIRC) have a freezer box on one side (with evaporator in there) along with adjustable holes to connect it to another box which acts as the fridge.

I bet you could make yours work the same.

I will see what I can do about some pics.

- CD