Don W wrote in news:m_6xg.134232
:


This weekend I measured the actual power draw on
our Cool Mate CLM12K (12,000 BTU) air conditioner
and found that it was drawing 12 amps at 124V AC
instead of the 9.1 amps claimed on the Dometic
website.


How much it draws is heavily dependent on its condensor temperature,
which changes the pressure the compressor has to work against. Monitor
its current and let it stabilize at 12A. Spray some water into the side
of the case so the fan can suck it into the condensor and watch the load
ease on the compressor.

The unit will probably draw less current after it has been running a few
hours so the case fills up with condensate water. There is a slinger
ring around the fan that blows through the hot condensor. This ring
picks up water from the pan it's built on and throws it up in the airflow
to the condensor, water cooling it with distilled condensate water from
the evaporator, exactly like a $99 cheap window air conditioner, which is
what the coolmate really is. Once the water supply has been condensed
and run outside into the slinger, it'll cool the condensor much better,
dropping your current drain.

It's also drawing more current because you're applying more voltage to
the unit than it was designed for, which doesn't really hurt it. The
plate probably says 115VAC, not 124VAC you measured.

If you're thinking about driving it with a generator or inverter, plan on
providing it with TWICE the running current drain, 24A AC, so you can
START it. It draws a LOT of current for a couple of seconds when it
starts. The genset must provide this starting power (the peak rating on
the genset) without tripping out or sagging voltage too far. A 3KW
genset is about right for this unit....but not a 1500W. I'm pulling TWO
8000 Btu LG Electronics Korean window units to cool my stepvan shop.
There's also a 2.7 cu ft R-12 fridge that starts all at the same time off
a Honda EU3000i electronic inverter superquiet genset mounted permanently
on the back. If it'll pull that load, it'd be great for your unit.

Now, put all that test equipment away, get a cold alcoholic beverage out
of the cooler and go sit in front of the Coolmate before you get a notion
to take the cabinet off to see what's wrong and screw it all up!