Installing
a Replacement
Refrigeration System
Having an installed freezer chest, that no longer
operates, can bring tears to your eyes if the beer is warm and the air
temperature hot. Our faulty freezer
was diagnosed with a leak in the refrigerant-gas piping, buried well within the
cold-chest … an expensive fault to fix requiring a complete rebuild of the
built-in freezer chest.
After researching the alternatives we decided to convert
from the engine-driven freezer system to a 12V battery powered refrigerator
system with an evaporator cold-plate that could be installed within the existing
built-in insulated frig-chest. We
thus purchased an Isotherm system (comprising electric compressor with
quick-clip mounting bracket, cold-plate, and thermostat control) and did the
installation ourselves.
The conversion was simple.
Initially I removed the old un-used and bulky engine-driven freezer
compressor, condenser unit and associated pipe-work plus filter.
For the new system I decided to locate the small compressor unit under
the quarter-berth next to the frig-chest.
The compressor unit mounted next
to the battery
A hole was drilled through the frig-chest wall, for the
frig-gas piping between compressor and cold-plate, and I then mounted the
cold-plate within the frig-chest and laid out the piping.
The cold-plate mounted in the
cold-chest
The compressor unit and thermostat control were then
mounted, and the piping between compressor and cold-plate connected (releasing
the pre-filled refrigerant gas into the cold-plate).
The 12V electric supply was set up, via the old freezer power-switch plus
fuse, and with battery power on and thermostat control set the new refrigeration
system started immediately. A final
tidy-up, sealing the frig-chest hole with expander foam, coiling / securing the
excess frig-gas piping, gluing a small thermometer inside the frig-chest … and
… job done.
Cost
of the pack was $1,032.00 (Sept 2004) and the installation took about 6 hours.
After
this first summer we are very happy with the results.
We pack pre-cooled and frozen food into the frig-chest for our weekends
or times away. The frig power is switched on as we slip the mooring lines and
its temp is down to approx 48C
after about 4 hours … and there it stays.
We have two separate 12V batteries, one for engine cranking and one for
boat-house use, so we keep power on to the frig continuously, and run the engine
for half an hour daily to keep the house battery charged.
So
… a frig just like at home with cold but not frozen food or beer .. and happy
boaties.
Some
technical details;
