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Jeff Jeff is offline
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First recorded activity by BoatBanter: Jul 2007
Posts: 42
Default August 7 - Land, HO!

* Wilbur Hubbard wrote, On 8/10/2007 6:46 PM:
....

I must inform you if your fridge draws 30 amps at 13VDC then there's
something seriously wrong with it. Mine only draws 5 amps. Hell, you
could run an air conditioner on 30 amps.


It would seem that we can add yet another topic to the long list of
nautical issues where you seem completely ignorant.

First of all, 30 Amps DC won't get you a lot of A/C, though I must
admit I haven't looked into to smaller units. (The smallest one West
has would be about 50 Amps DC for 5000 BTU.)

However, a 30 Amp draw is quite common for my type of fridge. Its a
1/2 HP motor driving a compressor that feeds several holding plates in
a 9 cu ft fridge and 5 cu ft deep freeze. The actual load varies from
20 to 35 Amps. Here in Maine I've been monitoring it carefully, and
it has taken about 40 Amp-hours per day for the last two weeks. The
fridge stays at 42-46 degrees, the freezer at 15-20, both measured at
the top shelf.

Your system probably has a Danfoss hermetic system and runs about half
of the time, depending on the load, so you actually use about 60
Amp-hours a day. And your fridge/freezer is probably half the size
of mine, and not as cold.

Frankly, I've been thinking that is I did my system today I might use
two modern Danfoss systems, so I could shut down the freezer when not
needed. However, the last time I charged it up I seem to have got it
right and the efficiency is quite high. I curious to see how it works
when we get back into warmer waters in a week.