In pondering what to get for a new refrigerator, I used my battery monitor to see how much juice each thing in my van takes. It is an interesting exercise. Here are the results:
|Item||qty/state||Amps for item||Watts|
|Baseline||un plug DC sockets, ant off||0.8||9.9|
|G4 LED light||1||LED||0.1||1.2|
|PS int. light||1||1 incandescent bulb||0.2||2.5|
|DS ext light||1||LED||0.3||3.7|
|Ext Porch light||1||LED||0.3||3.7|
|Roof light||1||Florescent – 2 T8 bulbs||2.1||26.0|
|Bath light||1||1 incandescent bulb||1.5||18.6|
|Water pump||Turn on||2.7||33.5|
|LP Water heater||Turn on||0.1||1.2|
|Inverter On||no load||0.9||11.2|
|DC Off||battery monitor itself||0.1||1.2|
The baseline is the battery monitor itself and the sensors (CO,LP,smoke), I believe. The watts are calculated based on the 12.4 V reading on the battery (watts=amps*volts). It looks like the battery monitor itself only takes 0.1 amp to run wired directly to the battery. The LED lights are clearly a big savings even over florescent. The LP appliances need a little juice to run. I guess that's the regulator or solenoid or something.
I've been looking at marine 12V DC refrigerators. It is looking like it will take a max of 35-50 amps per day to run one with a freezer compartment. Now, I have to get serious about what size to get. I found some Isotherm and NovaKool that will fit into the existing cavity with little or no modification. They also provide a little more interior volume because they are deeper than the Dometic that I took out.
BUT - if I took out the microwave and some or all of the tiny cupboard above it, I could get a bigger refrigerator and a sizable separate freezer compartment. That option runs on the higher side of the amp usage. So far, I've used the microwave only twice. I would really like having freezer space for my pet food and some for me too. I suppose I could stow the microwave somewhere for the occasional use I make of it. What to do?