Compressor fridge batttery charging.

[KOTSY]

Hi everyone, I am shortly changing to a compressor fridge with a 120amp. AMG  battery . My question is if not using solar ( which hopefully will happen when funds allow  early next year) what way do you think to keep my battery toppped up ?  Also which chargers or controllers best to use ? Sorry if it seems a complicated question but it seems complicated to me. Thanks again for any input. Cheers Pete.

[shepster]

Other than solar, and obviously electric hook up, theres little way of charging your battery.

You can run the motor I suppose but unless you have a dc to dc (b2b) charger fitted that will take a while or use a genny, neither of which would make you very popular!

Without a decent charging system the battery wont last more than a couple of days I reckon.

I personally use Victron solar controller and b2b with a Fogstar 105ah lithium battery but there are lots of alternatives out there.

[silverbullet]

AGM batteries should also be charged to a higher voltage than lead-acid ones, 14.4 volts iirc, might be higher.
If you don't do this the battery life will be significantly shortened, you need a dedicated "smart" charger.

[KOTSY]

Thanks for the replies. Thought I would have to charge up from hook up which is okay we will More than likely only stop a couple of nights without power ( not really off gridders ). Would like to put the battery under the back seat in my camper. As the 3/4 bed always stops down because our two little dogs sleep while travelling. Is there any way I could put on to charge without keep lifting the bed . Cheers  sorry for a numpty.

[silverbullet]

I have a Dometic CFX345 which ran quite happily in high temperatures off a standalone AGM for a weekend, however the fridge was under a tarp shade out of the van. I would say that you keep direct sunlight off the fridge itself, airflow and shade are your friends.
Get a dedicated charger for the AGM and you'll be fine.
No need to worry about outgassing as long as the battery is correctly vented as per manufacturers instructions.

[firetrader]

The JKF50 compressor fridge (Just Kampers) is said to only draw 0.7 amp per hour after settling down on start up (it takes about 5 amps to start up and get to correct temp then knocks on and off as required) so even if running a little more than a fridge you should get a few days off a lithium battery. Smart chargers are great and for my 10 amp per hour completely silent charger ( beware some make quite a noise), its ample when on a hook up.I have also bought a cheap portable 100 w  solar charger in case I am off grid (which is rare).So its worthwhile to decide on a plan, its all running ok and am away soon for 3 days so its going to have its first trial run.

[KOTSY]

Once again thanks for all your replies. It has helped a lot . Now to get going and get out in the camper again .Cheers