On Sat, 21 Aug 2010 21:53:42 -0500, cavelamb
wrote:

It has only been 110 for 30 days now...

I'd like to adapt an inexpensive window air conditioner to
built-in.

The first step was to make a door for the companionway that
the AC unit can sit in. It worked out pretty well, and the
top companionway board fits on top to close off the opening.
Slide the hatch closed and it cools right down!

But that means 1) climbing cover the AC unit to get in or out
of the cabin.

And 2) it blows tons of hot air across the cockpit.

The biggest problem (as I see it) is getting the hot air out.

I wonder what ducting would do to that hot side transfer.
It couldn't be good...
And I'd not like to cut a hole the size of a window unit in the hull!

So...

Marine AC units usually use a water bath to cool the condenser
coils. Pump fresh water into a tank holding the coils and the
warm water goes over the side. That means a hole in the hull with
a thru-hull valve on it for a pickup, and an exit hole above the
waterline.

The rest should be pretty straight forward.

Unless I'm missing something really big??


The woods are full of them in Asia (and probably other places). Most
of them blow in either the front hatch or a hatch on the cabin top
although I've seen them in the cockpit, as you describe.

Temperatures are probably hotter over here but hot air in the cockpit
is not a really important thing when the outside air temperature is
100 degrees or hotter..... you stay inside where it is cool.

A built in marine unit uses a water cooled "tube in tube" heat
exchanger for the condenser side, Usually mounted as a remote unit
with the compressor, probably in the engine room or other out of the
way place. The air handler is where you want the cold air.

It would be perfectly feasible to convert a window air con to a marine
unit by removing the condenser coils and fan and replacing them with
the water cooled condenser.

If you do envision building one be sure that you incorporate some sort
of high pressure and over temp shutdowns as sucking a plastic bag into
the water inlet is common. That shuts down the condenser side and will
kill the compressor after a while.

If you intend to mess about with boat fridges or air cons do try to
get a copy of Nigel Calder's book "Refrigeration for Pleasure Boats",
as it completely covers the whole subject from deciding on how and
where to put it to the size cooling pump as well as compressor
overhaul directions as an appendage.

Cheers,

John B.
(johnbslocombatgmaildotcom)