Small Residential Frig Current Drain Question

Thanks everyone, for some excellent info!

Comparatively speaking, very surprised how little 12vdc current the 3-way fridges use. However, I'd prefer not to worry about leveling issues and the high replacement costs---the primary reasons I'm looking at the residential units.

Encouraging to hear many 120vdc residential fridges don't draw nearly as much realworld current as we thought.

What are our chances of a daily, 24 hour duty cycle, composed of powering a small, residential frig, 20 hours on batteries along with 4 hours of generator runtime with a 160-200ah battery bank? This is assuming no other 12vdc load. We have a PD9260 that consistently produces 55 amps of initial charge current in bulk/boost mode.

I think the design is 50% duty cycle.. (Runs half the time) but the starting kick is big.

I would add more battery just to be safe.

See my test on a 4.5cf fridge a month or so ago.

http://www.rv.net/forum/index.cfm/fuseaction/thread/tid/28272254.cfm

My OFF-ROAD POPUP CAMPER Dometic RM2193 GAS-12VDC-120VAC pulls around 6-7 AMPS DC current when in 12VDC mode.



We always switch it ON about two hours out from a camp ground to get a head start on cooling it down when we start using it.

My unit does not have a freezer compartment per say but things mounted on the top shelf freeze up pretty good when in use.

I have seen a dual small fridge at LOWES for dorms that runs on both 120VAC and 12VDC. They looked like a nice unit to use.

Roy Ken

Our 120v only 3.2 cu ft "Igloo" fridge in the truck camper (replaced the 1981 Dometic three-way) draws 5 amps via inverter when the fridge is "on", which is about 2/3 to 3/4 of the time in 24 hrs.

So that is about 90AH in 24 hrs. In a recent five day off grid time, the 230w of solar was able to keep up with the fridge draw, but it was a nail-biter to get enough sun each day. Got to have a way to recharge the batteries on a cloudy day.

The solar has to put that 90AH in during the day but the fridge keeps working at night, so the solar has to be able to do way over that 5 amps, even with no clouds at all during the day.

Meanwhile the rest of the rig's 12v stuff is also drawing down the batteries, so you are falling behind slowly every day till your bank is at 50%, then you need to do a generator or shore power recharge to catch up and start over.

I posted something about the 3.2 fridge draw tests I did a couple months ago if you can find that thread.

Best test will be in your driveway. Measure the battery voltage every 30 minutes. Voltage down to 12.0 to 12.2 is about the minimum you should run.

The real trick is to add battery so it can last 24 hours and enough solar so the batteries are fully charged before the sun sets.

The 3.5 cf R3800 Nova Kool compressor fridge draws 2.2 amps at 12 volts when running. No inverter needed, less power required.

http://www.novakool.com/products/single_doors/r2300_3800_4500.htm