Battery Life With a Residential Fridge

Adam H wrote:
I don't think there is an issue with adding a third battery as long as it is in good shape. Batteries are not smart and really don't care about mixing and matching, I will test it again when I'm done after I let it sit untouched for a week. Not positive I will be adding it until I do that test. The fridge is a Black and Decker 4.5 cu/ft apartment fridge. I have had it for 2 years now as a spare, it is about 18in shorter than the Dometic it is replacing. Looking forward to the added shelf above the fridge. Ideally a taller fridge would be better and when I get one I probably will do another install, but I have this and the fridge part is larger than the Dometic fridge but the freezer is tiny. Since it can hold my ice cream its large enough for me.

Doing the stress test today since I am home on kid patrol all day. Charged battery last night and have been running the fridge for 8 hours now

Open circuit voltage is 12.52 and running is 12.40
Let's see what it looks like after 10 hours......

I will stop when the OCV is 12.0v

You should be fine.

I run my 10 cu ft home fridge from one pair of 6V GV batts. I have no trouble with that setup while traveling or overnighting..

Traveling the tow vehicle charge line helps to offset some of the energy being used by the inverter and the fridge..

At night I have had no problem running the fridge, plus some halogen lights for a couple of hrs and even running the furnace all night long and still have plenty of battery left in the morning..

Although I must note that the inverter I used is a Tripplite PV1250 which is a MSW with a load sense feature that allows the inverter to shut down the output when no AC load is present.. So when the fridge is not calling for cooling the inverter shuts down saving at least 20-25 Ahrs of battery capacity per day.