I’ve had the compact Isotherm air-cooled unit installed for a season now. My ice box is a About 4 cubic feet and has the original 1970 low-density foam insulation
, except there was none on top, so I glued an inch of high-density foam under the top and lid. And put a valve on the drain hose to stop cold air from dumping into the bilge
When the weather
is hot (ca. 100°F) the unit runs for about five minutes and rests for about 15 minutes. Current
draw is about 2.6 amps. The batteries
can handle it for days on end without recharging. The unit is installed in the sail locker just on the other side of a bulkhead from the icebox
. There is no audible sound inside the boat, except a small “click” from the thermostat when it trips. Sticking your head
into the sail locker, you can barely hear the fan.
Cold drinks all summer without schlepping ice. Very happy.
I should add that at the location where the condenser unit is installed, suspended on its bracket in the mechanical area, near the waterline, it naturally draws cool air up from the aft bilge
and warm air exits out a vent higher up on the coaming. When I put my hand in front of the fan, I feel cool air (not warm air) coming out.