How long should a full charge of house batteries last?

[Rolling R]

I have a new Thor Palazzo 33.2 with a residential refrigerator. The coach came with 4 house batteries... questions for anyone who knows:

1. What is the total amp/ hours for the 4 house batteries from the factory?
2. How long can I expect a full charge to last running the resi fridge and a couple of lights?

I am currently facing problems with (I'm assuming) my auto transfer switch, so I can not even plug into shore power... shutting off my gene at 8 p.m., I'm finding that my fridge may run until 7 a.m. the next morning OR cut out by 3 a.m., leaving it to warm up until 8 a.m. (when most parks allow the genes to be fired up)...

Does anyone have experience in this regard? I'm really disappointed that I can't get 12 hours of fridge power out of the factory engineered system... I really should have done more homework if this is the case. Maybe I'm just not doing something right... any feedback would be appreciated. Thank you.

[16ACE27]

I don't know the answer to your question but in your situation I would get a 10 amp minimum battery charger and extension cord and connect that to my batteries when the generator is off.

[Metalman]

Since I have no experience with residential refrigerators I can't give you anything other than I expect that you won't be able to power your refrigerator much more than overnight without the generator or shore power. I had a problem with my shore power not charging, yet my generator didn't charge the coach batteries. Under the dinette seat where my transfer switch and other electrical equipment is located, I found a device that had two loose 12 volt connections. They were large diameter ring connectors. Once I tightened them my generator charged the house batteries.

[Rolling R]

Thanks- that could be a good back up plan!

[Rolling R]

I just found out from my RV tech where my switch is located. I'll pull the panel and check the wiring for lose connections. I think I also read something in the manual about trouble shooting that unit. Thanks for your feedback!

[TurnerFam]

Interesting question, and one that we all have different experiences with -
though, there's no 'standard' amount of 'time' that your four 6v batteries, at 'full charge', will power the Fridge and several lights.

First - the fridge is not just a constant draw. It is ON when it needs to bring the temp down. And the light comes ON when you open the door, of course. Your TEMP setting will impact this power consumption and run time, the number of times you open the door during that time, AND the temperature and weight/number of items you are cooling.

Second - the batteries are being used by more than just the fridge, of course, and any lights in use will impact the usable 'hours' for your batteries. Remember, also, that 'silent' items that draw power are sometimes easily overlooked, such as device chargers, TVs, even when not used, the Inverter itself, fans, and anything else that might be plugged into an outlet out-of-sight, or mind!

Third - the batteries themselves have a certain lifespan(number of charges, discharge cycles, etc) and the age of yours will weigh in on hours of usable power.

Note: the usable hours of Fridge power, and any items powered through the Inverter, also can be controlled, or limited, by you to also preserve battery levels through the night - the LBCO(LowBatteryCutOff) setting on your Magnum Inverter display allows you to tell the Inverter when to 'ShutDown' when the batteries reach a critically low level, such as 11.5 or 10.9, whatever Voltage level that you don't want it to go below. This preserves the ability for your batteries to retain enough power for you, or the AGS, to crank the Generator later, or in the morning, etc.
(this does not apply, though, to strictly 12v items, such as lights, fans, 12v TVs, etc., as they run directly from the batteries)

Some suggestions to get through your situation might be that even if your Fridge were to be turned OFF during the overnight hours, you'd still be ok in the morning, OR for the last several hours of generator usage, run the TEMP setting on the fridge to as low as possible to get it as cold as possible before the overnight hours : )

Some of us may get 12 hours of Fridge power from the batteries with no problem, others may only get 5, etc... it's not an exact game, as in any electrical usage scenario, it all depends on so many variables - even the outside and inside temperature of your coach is going to impact it.

[djcarter]

And once your batteries are done upgrade, since you have a nicer coach maybe you have better batteries but the ones that come with lower end units are pretty poor. Getting switch fixed should not be difficult 1/2 job to swap out the part, could do it yourself but depending on location could be a pain and the service dept is probably swapping one out every few days for a customer...the problem is that prolific.

[ZaN_RV]

So I have MagWeb unit in mine so that I can micro manage it. I also have the Battery Monitoring Kit. I have the standard batteries that came in my 33.3, but I have upgraded the inverter to the MSH-3012. If my batteries are at 100% and for the most part the only thing I have running is my Mobley, Wifi, and fridge, then I get down to about 48% SOC in 24 hours.

I don't want to post it publicly, but send me a direct message and I can give you access to my MagWeb. You won't see too much honestly, but you can take a look.