It seems my batteries are not running my fridge very long. Two new deep cell batteries were installed last year and would run the fridge for several hours. Seems like this year my batteries will only run the fridge for a couple hours as we travel. I believe all devices that utilize 12volt are shut off and only fridge drawing power. Not sure if they are not fully charging while on shore power or if something could be draining them. Looking for suggestions on things to check.
Our Samsung refrig has an ECO setting that is suppose to use less power from the batteries while towing. May want to see if your unit has a similar setting.
I’ll look into that. I can’t help but think something is going on cause it would run 8 to 10 hours before but I’m lucky to get 3 or 4 now.
Have you verified individually that your batteries are good? Levels are good? Connections are tight. Seems odd 1 year old batteries would go bad unless they were not properly maintained. On shore power do you see that the Voltage increases, thus the sense a charge is in progress from the converter?
I agree with Eramsey. Really need to verify the state of the batteries with a load test, not just a simple voltage meter reading. Confirm the electrolyte levels and specific gravity readings for each cell in both batteries. I’d also recommend a good monitor such as the Victron BMV-712 so you can monitor battery charge effectively. You’ll be able to easily see when the battery is being discharged and charged and the rate of each.
Is this an RV fridge or residential? An RV fridge usually runs off of propane but does require 12V DC for the control board or can run off of 120V AC. I used to have an older Dometic RV fridge that was a 3 way (12V, 120V & propane) but don’t see a lot of those types anymore. A residential fridge would require an inverter to power the fridge. That will take the 12V DC from the batteries and invert the output to 120V AC to power the fridge.
There’s probably a few 12V items still drawing power, like radios, CO/Propane detectors, system control panel (lights, slides, HVAC). The typical lead acid batteries are limited in their capacity and usage. Each usually have about 80Ah and connected in parallel would get you about 160Ah of capacity. But you should never draw that capacity down below 50% or 80Ah. Using more than 50% of a battery’s capacity will reduce its usefulness. Another great reason to have a quality battery monitor. You should have 80Ah available for use with the batteries fully charged which equates to 960Wh. You can check the fridge specs (voltage, wattage, amperage) to see how much power it draws when in use and then do some simple math to determine how much run time you should be getting.
There is a possibility that running the fridge off those batteries for 8-10 hours previously had run the batteries below that 50% and the batteries have lost some of their capacity.
2 Likes