How about a compressor cooler like the ones Waeco sells? They take a bit of
power (30 Ah ?) but can be turned off and they will be a handy backup. They can
even be switched to freezer mode and used in a car.


http://www.waecoadlerbarbour.com/


"Glenn Ashmore" wrote in message
news:K_pTc.28301$Jo1.18335@lakeread01...


Richard Kollmann wrote:
Glen, Check this out http://www.marineair.com/marineair/pdfs/evap.pdf

From the author of four books on boat refrigeration
http://www.kollmann-marine.com

Hey, Hey! I knew you would come up with something. Looking at the
specs for those plates though made me go back and figure the BTU loads.
Drink coolers are a real challange. Not only do they gain heat at the
same rate or faster than a frige but they are constantly opened and
closed and being loaded daily with more warm drinks. Also in the
cockpit they get a lot of radiation load. OTOH, being full of cold
water it will not gain as much heat every time it is opened.

Roughly figuring a 2.1 cu.ft. box (14Wx12Hx22L or about 10 sq ft of
surface) with 3" of foam (R=16) will gain about 600 BTU/day with a 40F
delta-T. Half again that at least for frequent openining and radiation
load so say a 900-1,000 BTU/day base. A case of beer weighs about 20
lbs and to get it from 75F to 42F will require an additional 660 BTUs.
Figuring a case and a half of drinks a day for a crew of 6 makes about
1,000 BTUs. All totaled that will be about 2,000 BTU/day or close to 80
BTU/Hr. If I stock it each evening the load should stay pretty steady
between 70 and 90 BTU/Hr. To maintain the box at about 40F the coil will
have to be running about 26F. That would make a BD35 at 2,500 RPM run
about 15-20 minutes an hour on average. That would be OK for the
compressor but I would be pushing the evaporator at a rate of about 270
BTU/Hr. I don't see how I can do that with those plates.

--
Glenn Ashmore

I'm building a 45' cutter in strip/composite. Watch my progress (or lack
there of) at: http://www.rutuonline.com
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