by Tom Neale
This is a continuation of Tom's Tips from his section of
web site. Go to his section there for many more tips on this
subject and others.
1. Never bend the copper tubing that transports the refrigerant,
unless you are using proper bending equipment. This can crimp
the tubing and hinder passage of refrigerant and this can
damage the compressor. Attempts to straighten out the crimp
will often make it worse. Sometimes this will occur accidentally
when people are working around the lines. Make sure any mechanic
working on your boat knows where these lines are located.
2. If a refrigerator or air conditioning compressor has a
raw water heat exchanger, this may be the reason for diminution
or total loss of cooling. You'll know if yours has a water
heat exchanger by the coil of tubing on or near the compressor
and the fact that a water pump will be pumping water from
a through-hull to the tubing. Usually marine air conditioning
units and larger refrigeration compressors use this system.
Of course, you already know that if your strainer or through-hull
intake is clogged, or if your pump is defective, you've got
a problem. But also remember that, in time, the inside of
the cooling tubes may have deposits build up on them, of sufficient
thickness to impair the heat exchange. Depending on the type
of metal in the coil and in the refrigerant tube that passes
through the coil, there are various products that you can
pump through the heat exchanger coil to clean it. Consult
with the manufacturer to learn what works for your unit. This
is often a job that you can do yourself. Smaller units, such
as dedicated ice makers, may be cooled simply by a fan moving
air over fins. If you have fan cooling, check to see that
no dust or other obstructions are interfering with the air
flow over the fins, and, of course, that the fan is operating.
(Careful of your fingers.)
3. Whenever you add refrigerant to a compressor be sure
you're adding it to the correct port. If you add it to the
high pressure side, you could cause the can to explode with
devastating effects. Check with the manufacturer to be sure
that you know which port to use.
4. In all cases, disconnect power source unless you must
run the unit, and then be careful of dangerous electric shock.
5. I'm not a refrigeration mechanic and you should take these
only as general comments about things that I've observed as
a layman who's had to deal with refrigeration gone bad while
out cruising and who doesn't like spitting cockroaches.