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Bruce in Bangkok[_6_]

In article ,
says...
Jon,
Good info. The cold plates I have bought are used units and they all have
the expansion valves with them. I have assumed they also have integral spray
orifices. I suppose I could apply compressed air to determine approximate
flow rates. How else would I test these, as they are not able to be
disassembled? The cold plates are used marine units and I want to use them
for a freezer, not a refrigerator, hence the -40 requirement. I am aware of
the requirement to change the medium in the cold plate itself in order to
reduce the temperature of the state change. The goal is to freeze the plates
down once a day or less when in use. How do I estimate the heat load? The
cold plates are aproximately 24" x 18" x 4".
Steve

"Jon Elson" wrote in message
...

Steve Lusardi wrote:
I wish to use a single large compressor to service 3 cold plates and 3
air conditioning evaporators, but I am not a refrigeration expert, so if
my thinking is incorrect please let me know. Each one of these (users)
will have their own mechanical temperature controlled evaporator valve. I
assume the compressor should be cycled by head pressure with an overtemp
sensor for safety. I would like to use a salt water cooled condensor on
the high pressure side and a freon gas that changes state around -40 C.
Please advise. Do I need an accumulator of some description on either
side? If so, what? Each one of the users have 3/8" in/out tubes. How do I
size the compressor? Any tips or books on this subject would be welcome.
Steve

Somehow I get the idea that you are building a "boat installation" in
which case try to lay your hands on a book named Refrigeration for
Pleasureboats: Installation, Maintenance and Repair by Nigel Calder.

It gives you methods and formula to calculate heat and insulation
values, condenser water flow, cold plate area and everything else you
need to design and build a refrigeration system for a boat.

Even tells you how to build your own condenser using either copper or
Cupro-nickle tubing.

--
Cheers,

Bruce in Bangkok