Glenn,
If it is a condensor, then the liquid refrigerant should carry the oil
along and should not pool in the turns of the coil (notice please the
"shoulds"). But I like th idea as you have it because:
-You have separate turns so a damaged turn could be eliminated from the
circuit.
-You may decide to rework the refrigation to be reversable and so
provide heat from the pond at little cost.

Just be sure that you keep the keep above freezing in fresh water. If
this idea appeals to you, you migth think of putting a little loop like
a trap at the outlet end just before the lift so the oil has someplace
to collect a form a big enough plug so it gets lifted out of the cooler.

Sounds interesting - I'd love to hear how it works out.

Matt Colie ex reefer guy (among the rest)


Glenn Ashmore wrote:
"Matt Colie" wrote in message
...

Glenn,
Are you planning to us this as an evaporator?
Matt Colie


No. It will be the condenser. The evaporator goes in the refrigerator.
The keel will be cold enough already. :-)

The down side of casting a condenser in the keel is that it is an extremely
permanent installation. No way to fix it once it is done so I added one
extra loop. If one of the working loops springs a leak I can just switch
over to the spare. I have had them pressurized with nitrogen to 250pis for
3 months now so hopefully they will not leak once they are inside the lead.

The loops are a continuous downward slope so the oil will pool right at the
return end. Probably could have made it a bit more efficient with a larger
OD tube to slow the refrigerant down, get more surface area and less
pressure drop but I read so much about oil getting trapped in the condenser
and starving the compressors that I got scared.

--
Glenn Ashmore

I'm building a 45' cutter in strip/composite. Watch my progress (or lack
there of) at: http://www.rutuonline.com
Shameless Commercial Division: http://www.spade-anchor-us.com

"Matt Colie" wrote in message
...
Glenn,
If it is a condensor, then the liquid refrigerant should carry the oil
along and should not pool in the turns of the coil (notice please the
"shoulds"). But I like th idea as you have it because:
-You have separate turns so a damaged turn could be eliminated from the
circuit.
-You may decide to rework the refrigation to be reversable and so provide
heat from the pond at little cost.

Just be sure that you keep the keep above freezing in fresh water. If
this idea appeals to you, you migth think of putting a little loop like a
trap at the outlet end just before the lift so the oil has someplace to
collect a form a big enough plug so it gets lifted out of the cooler.

Sounds interesting - I'd love to hear how it works out.

Matt Colie ex reefer guy (among the rest)


Glenn Ashmore wrote:
"Matt Colie" wrote in message
...

Glenn,
Are you planning to us this as an evaporator?
Matt Colie


No. It will be the condenser. The evaporator goes in the refrigerator.
The keel will be cold enough already. :-)

On Fri, 10 Mar 2006 13:23:26 -0500, "Glenn Ashmore"
wrote:
The loops are a continuous downward slope so the oil will pool right at the
return end. Probably could have made it a bit more efficient with a larger
OD tube to slow the refrigerant down, get more surface area and less
pressure drop but I read so much about oil getting trapped in the condenser
and starving the compressors that I got scared.

Glenn, did you give any thought to circulating water through the keel,
and then using that to cool the condenser? That would allow you to
use a combination air and water cooled condensing unit, and if
anything went wrong with the keel loop (and I'm concerned that it
will), at least you have the air cooling as a backup.

The idea was to avoid the circulating pump. If the whole thing craps out I
can always add a couple of conventional tube-in tube condensers and pull
seawater off the sea chest. I plan to keep the vacuum pump, extra
refrigerant and HVAC tools on board. Should be good for a few free beers
from fixing systems on other boats if I ever get down island. :-)

--
Glenn Ashmore

I'm building a 45' cutter in strip/composite. Watch my progress (or lack
there of) at: http://www.rutuonline.com
Shameless Commercial Division: http://www.spade-anchor-us.com

"Wayne.B" wrote in message
news
On Fri, 10 Mar 2006 13:23:26 -0500, "Glenn Ashmore"
wrote:
The loops are a continuous downward slope so the oil will pool right at
the
return end. Probably could have made it a bit more efficient with a
larger
OD tube to slow the refrigerant down, get more surface area and less
pressure drop but I read so much about oil getting trapped in the
condenser
and starving the compressors that I got scared.

Glenn, did you give any thought to circulating water through the keel,
and then using that to cool the condenser? That would allow you to
use a combination air and water cooled condensing unit, and if
anything went wrong with the keel loop (and I'm concerned that it
will), at least you have the air cooling as a backup.