Building an Ice Box & Refrigeration

[Terry Etapa]

I'm going to be building an icebox this winter. After not finding much information using the "searchy thing", I thought I'd post my questions.

I'm interested in any information on the various brands of refrigeration systems. Information on the differnt types, such as keel cooled, water cooled, air cooled, etc. Personal experience is worth so much more than glossy brochures from a dealer.

What types of insulation, along with the thicknesses used, work well? Is the value of "super insulation" worth the cost?

Any help on construction and design of the box and lid would be great.

Finally, how big? What about freezers?

Thanks in advance,
Terry

[Karl A. Hilbert]

Parker's The Sharpie Book has a bit on box construction.

[Ross M]

Glenn Ashmore Rutu Online (http://www.rutuonline.com/) seems to know an aweful lot about this subject. He hangs about on the Rec.Boats.Building newsgroup - you might drop a note there...

Ross

[mmd]

Our hosts' sister publication, Professional Boatbuilder, has a two-part article by Nigel Calder on marine refrigeration that started in the last issue (No. 90) and concludes in the current issue (No. 91). Well worth the price of a back issue.

[slacker]

Go here, http://www.westsystem.com/ and search "ice box". Step by step construction, nothing on refrigeration however.

Darren

[paladin]

I would say yes to the "super insulation" but also if you have room to have at least 6 inches on all sides...top and bottom.....and use a water cooled refeer system, the current (power) requirements will be less. You can make a freezer if you wish....then bore a 1 inch diameter hole in the wall between the freezer section and the refrigerator and install athermostat on the opposite wall to operate a small "microprocessor" size fan....also a couple of small fans in the freezer and reefer sections make the system nore economical...the fans will draw about .05 amps at 12 volts...a flashlight battery will perate for a few days.........and will keep all stuff evenly cold..
Also a cold blanket inside the cooler will extend the cold and reduce power drain......and when you come on board or will depart on weekends etc...freeze water in jugs, bring them along, and place them in the freezer/reefer......cold water as it melts and keeps the rest of the goodies cold......and so much more.....personally, I would look at Glacier Bay, depending on the size of your boat and it's intended use...

[Figment]

Beware that polyisocyanurate (aka "superinsulation") is an open-cell foam, and as such it suffers from significant performance loss once it gets wet. Though I don't have the hard data in front of me at the moment, I think it's something on the order of 60%.

If you can construct the box in such a way as to protect the foam and keep it dry, polyiso may be the way to go. Personally, I think that good ol' extruded polystyrene (closed cell foam, non-absorbtive) is better over the long term.

[paladin]

My apologies..Figment is correct...I assumed that you would make or have made a suitable epoxy/glass liner for the box innards.....and also an adequate drain at the bottom with a short loop just below the box to provide a drain but block cold air....

[Klaus]

Terry, it either has to be an ice box or a refrigerator, not both. Refrigerators usually do not have a drain cock at the bottom, no need for it.
I built a refrigerator into a bunk locker in my NIS26. Originally I thought I'd get by with a camping type Engel fridge but it was way too power hungry for the solar panels to keep up with it.
So it was an expensive Isotherm fridge unit that was chosen as a replacement. This eutectic unit apparently can cool up to a 120 litre volume, in my fridge its only about 1/4 of that and consequently a very efficient fridge. It runs about 4 hours in 24 on a hot day at anchor.

Insulation was fitted in layers of 25mm polyurethane foam (got it cheap as offcuts from a boat builder). My boat is of plywood construction. First layer was 'astrofoil' (a roof insulation product - like bubble wrap covered with alfoil on both sides). Then 3 layers of the foam on the bottom and the sides of the box, individually fitted so the corners were staggered.
The lid has 2 layers of this foam.
This was followed by another layer of 'astrofoil' and then lined with 3mm marine ply, epoxied to form a watertight box. The top is the modified original bunk locker lid (top loading locker).

The compressor is fan cooled, it is very quiet. The extra money for the water cooled version was not justified in my case, besides, I did not want a hole in the hull for it.
These isotherm fridge electronics can generate radio interferance, mine certainly did, but I have at last found a fix for that. Performance of the fridge is ecellent.
Klaus

[ion barnes]

Gentlemen! Blue styrofoam and epoxy. The only way to go!

[Thad]

There was an article in WB a few years ago that shows a good icebox construction. Mar-April 1991, v. 99, p. 74.

[brad9798]

My old icebox was converted with a household refrigeration unit ... place below the box just foreward (2') of my starboard engine ... easy to place a platform there ... good ventilation, etc.

Works like a charm.

[Terry Etapa]

Thanks for the starting points in my research into building a refer system.

I've got a few additional questions.

By "super insulation", I was refering to the vacuum sealed panels. They seem to be very expensive. Are they worth it?

Klaus - By "ice box" I mean the insulated box in which I will install a refrigeration unit. I've been told to install a drain in a refrigerator if you have a top opener. This allows water to be drained after cleaning out the box. Couldn't you just use a sponge? Is a drain a good feature?

Can polyisocyanurate foam be sealed up to keep out the water? Does closed cell polystyrene need to be sealed?

I'll be looking for the issues of Professional Boat Builder and Woodenboat this weekend. Maybe my questions will be answered there...

[mmd]

Terry; A client of mine had the icebox in his Herreshoff "Mobjack" built with vacuum panel insulation and is pleased as punch with it, but 1.) space was limited so any savings in volume were needed, and 2.) he was fortunate enough to be in a position that cost was not really an issue. To my sensibilities, the cost is extravagant enough that they are to be specified only when all other options are exhausted.

A drain hole is a convenient thing to have when it's time to de-stink the icebox, though I prefer to not have it drain overboard. Usually the icebox doesn't extend from counter-top to sole (if so, you have to do some pretty athletic contortions to reach those spilled peas at the bottom), so a drain in the bottom fitted with a shut-off valve allows space for a plastic dishpan to be slid underneath to drain out the soapy wash-water and disposed of manually. A "sock" of husehold closed-cell foam pipe insulation with a jacket of heavy cloth secured by a velcro strap will insulate the valve and prevent any condensation drips.(A friend uses one of those cloth-covered neoprene beer bottle jackets for this purpose with great results.)

My usual specification is to lay up a fiberglass liner for the icebox and set this into a rigid foam lined locker. It can be treated like a shower liner when it comes time to drill holes for drains, coolant lines, etc., and a bead of caulking at all openings and the perimeter keeps moisture away from the foam insulation. If it leaks, the whole unit can be disassembled and the foam replaced. I've had clients request copper and stainless steel liners, too. Insulation is preferrably 4" thick if you want things to stay cold and use little power or ice.

[Terry Etapa]

The number of brands, and their features is still confusing. The local marine electrical supply sells frigoboat. They seem economical enough compared to the Glacier Bay models. Thoughts? Experiences?

[Ronin NW]

How timely; I've got a few icebox issues of my own... Here's the situation, and then I'll get to my questions.

When we bought RONIN, the former owner had just started a icebox-refer conversion, but only got as far as cutting a hole in the back of the icebox (adjacent to the engine). This is a *very large* icebox, two levels, with vertical access doors behind and directly below the galley sink (facing aft), and ice stored on an intermediate tray in line with the depth of the sink.

I for one don't want the trouble of a referigerator, and would rather just buy ice (and having been doing so for months quite happily... oh yeah, we live aboard). It's time to properly seal up that hole though, and what I'd like to do is install another access door to load ice through the back side, without having to remove all of my food from the top portion of the icebox. It appears (from this hole) that the icebox construction consists of two layers of 1/2" plywood with a whopping 1" of closed-cell foam between. Not much, I'm sure. I need to rebuild part of the existing hole, and remove a bit above the hole to create a 13x20" door.

Could I simply build up the icebox on the inside to increase the insulation without having to rip the whole thing apart?

The bigger question: what about drainage for ice?! I've searched high and low, and nowhere have I found any mention of this. There's a 1/4" outlet, which was running straight to the bilge (ack! freshwater constantly flowing into the bilge?!), so I've attached a hose to that and 'frankenstein-ed' together a small bilge pump into an in-line pump, which draws the icebox meltoff into my galley sink (home dishwasher-style) and then out the sink's thru-hull. I was advised not to put a small bilge pump in the icebox itself (creating warming heat and a headache of wiring). This is, however, on a manual switch, so sometimes allows lots of water to accumulate before I turn it on. My newest scheme (not yet employed) is to put a small sump tank under the icebox, which it will drain into, containing a normal bilge pump on a float switch, draining either into my galley sink or spliced into an esixting thru-hull drain hose.

Does this sound crazy? Logical? Has everyone been keeping it a secret how they handle this meltoff? Sorry for the long post, but this has been weighing on my for a while.

-Scott

[ohiomike]

hi
dont know if this will help but here it is..
a guy at my marina has an older fiberglass lyman
and he bought one of those mini frig/freezers from an apliance store cut it all up and retro fitted the parts into a custom built frig. very well insulated he can keep our beer cold all day while were out on fishing trips. so for us guys who dock and use dock power its great he did install a drain hole cause of the freeze and thaw it creates alot of water

he installed a simple drain trap and taped in to a deck drain that go to a thru hull fitting

the condencer and evaporator very compact all fit with out opening the refrgerant system maybe someone here can use this on one of there projects

best of all the frig/freezer he bought only cost him about 150 dollars

[Lone Star]

Here's some good information...

Project (http://www.boatelectric.com/Nova%20Box%20Building%20Plan%20for%20the%20LT200-F%20Kit.htm)

[Terry Etapa]

I was told about rparts (http://www.rparts.com/). It's an online refrigeration catalog with discount prices.

[Terry Etapa]

I was looking at Waeco / Alder Barbour units at Scan Marine in Seattle. The guy there showed me a prebuilt drop in unit (Coolmatic RPD-190). His take was it uses the same components as the icebox type systems, so why not let the factory build the icebox for you. His point was well taken, it cost $1250. I was a bit concerened about the lask of insulation.

Anyone have experience with these? Could I just build in insulation around the installed unit?

[ 10-27-2004, 02:46 PM: Message edited by: Terry Etapa ]

[paladin]

..without knowing all the specs I would bet that it's not very efficient and will consume large amounts of energy just like a household unit...and you need plenty of ventilation for the excess heat...

[Terry Etapa]

Here are the specs from WAECO (http://www.waecousa.com/):

Gross Capacity: 6.6 cubic feet / 5 cubic feet in refrigerator 1.6 cubic feet in freezer compartment
Voltage: 12/24 volts DC, 110/220 volts AC
Power Input: 65 watts
Running Time: (aver.) 30% at 68°F ambient temperature, 45% at 86°F ambient temperature, both at 41°F interior refrigerator temperature
Power Consumption: power input x average running time
Insulation: CFC-free polyurethane foam
System: fully hermetic Danfoss BD50F compressor with integrated control electronics, low-voltage protection adjustable for storage or starter battery, electronic fuse/automatic reverse pole protection, integrated mains supply unit with priority switch mode for 110 to 240 volts, dynamically ventilated air outlet, evaporator formed from behind, manually adjustable thermostat

[Dale R. Hamilton]

Gee whiz- why don't you just go out and buy a frige/freezer made for the RV industry. I just bought a beauty- 6.3 cu' Norcold, $926- runs on propane or 110, buy you can opt for 3 way, runs also on 12v.

[Spissgatter W-9]

Well, I tried to build an ice chest a la Gougeon Bros. By the time I had 3 inches of insulation all round, I didn't have room for a six pack of beer... maybe a 12 beers loose with a little ice. Granted I have a narrow beamed boat ( 8'6"). So, I bought a 60 qt Icey Tech ice chest. Spendy, but fits in the same space. It comes with two drains. If it lives up to reputation, then should work out at least as well as the home made version. Also, you may want to check out the latest issue of "Boat Works" (fall). It has an article on onboard refrigeration that I think u will find relevant if not useful.

[cbob]

Terry, For what it's worth, I once increased the insulation of a 10 Cu. Ft. ss lined top loading ice box with 1 in. thick layers of urathane foam, inside and out, total 3 to 5 in., using for guidence, a book by Spa Creek, Annapolis. Ended up with about 5 Cu. Ft., but it kept ice 300% better (15 days in mid Pacific) than the original 1 in. of Celotex which remained, sandwiched. I found this book to be the resource I needed, adhesives, insulation, and why, and practical details. Someone out there may have more info on this on this book, 8 x 11, spiral bound, orange cover I have lent it, sob, so can't provide more details or find them in the search thingys.
Some major considerations are type of usage, availability of ice, space, type of power, 110 AC,12/24 V DC, engine driven, battery charging, solar cells, and anticipated ambient temperatures, as applicable to your situation. If you go past a a well insulated box with ice, you will have some system engineering to do to make it come out right. Those 12 V. jobs need good ventilation or water cooling, and are juice hogs.
Luck on this, cbob