Alternative Fridge?

My Black & Decker charger pictured, has these 5 modes.... 4, 10, 20, 40 amp, and Start.

During trips, to shorten generator run times, I set my B&D charger to 20 amps.  I worry that 40 amps is too hard on the pair of batteries.  I am comfortable with 10 amps per battery.  The 40 amp setting is handy for emergency use.

Decades ago now, my original Ford chassis battery was showing signs of weakness when we headed out for a wedding about 350 miles from home.  On the way back home, the battery completely died in a rest area.  To get the V10 chassis engine started, it took the Onan generator running, jumper cables from the house batteries, and my battery charger at the 40 amp setting, to start the V10 engine.  So there was just that one time where 40 amps was extremely handy.

I could not get the charger's Start Mode to work.  Maybe I wasn't working it right.  Maybe the unrecoverable battery prevented it from contributing.

Sorry for drifting off topic.  At least you started this thread and the drifting from it. 

lol.   That I did Ron.  I figured it’s all related to swapping to a 12 volt fridge so keep it in the family with one thread.    Thank you for the info.   

Looks like I will need to run a 10awg wire from the battery to supply a conversion.  They say a 12 gauge (that’s what’s there now) may suffice but I won’t know till installed.  I’d rather see what it’ll take to string a new lead first before spending the money only to learn I can’t get it done because of wiring route. 

I’m waiting to hear from my doc on how to go forward on new cancer diagnosis.  Seems once you have cancer (4 years now) you’re constantly chasing it.  Anyway as soon as this all starts I will post how the conversion / repair goes and turns out. Good or bad.

Joseph,
A thought occurred to me on your heavy duty wire to provide 12 volts and ground to the replacement... I would search for a "high strand count" cable with silicone (or rubber+silicone) coating. This combination gives the most flexible motion and longest wear life since this needs to move every time the slide goes in and out.   I've done some robotics work in the past decade and this is what they use,,, but much thinner, of course, specifically to endure the motion, vibrations, etc.


The down side is that silicone is slightly more prone to damage so you should consider adding some heat shrink around any spot that might rub something else.


Larry

I’m waiting to hear from my doc on how to go forward on new cancer diagnosis.  Seems once you have cancer (4 years now) you’re constantly chasing it.

Sorry to hear of your health history.

I am in a similar situation.  As of October of last year, after chemo was completed, I am supposedly in remission from stage 4 DLBCL (diffuse large B cell non-Hodgkins lymphoma).  I go in next month for another round of quarterly bloodwork and biannual CAT scan to make sure it has not returned.  In the mean time, I continue to recover from the chemo treatments.  I can't yet go hiking like I used to, still limited to casual walks on flat surfaces.  But the hardest challenge for me is avoiding sugar and starch to starve potential returning cancer.

There we go, changing the subject again, ha, ha.

I’ve installed the 12 volt conversion. Took all of 3 1/2 hours.   100 degree day  the fridge cooled down to 10 degrees in freezer and 40 in fridge in a bit over 3 hours.  It’ll need to run a bit longer to get the fridge colder.  I’m still figuring out the settings to dial it all in. 

They had told me I may need to run a 10 gauge wire if the wiring wasn’t heavy enough.  I didn’t want to get stuck with having to figure it out after the install so I did that first to be sure I could.   That took an additional hour but wasn’t that difficult and in the end wasn’t needed.  I left it in place even though it’s not hooked up.

On our last trip prior to the conversion my batteries failed and the only option was a couple 12 volt marine maintenance free batteries from Walmart.  They are supposedly 100 amp hour , so 200 all in.  On a 100 degree day I get roughly 18 hours of my fridge before 50%. I think it’ll go longer after due to the fridge requires more power in the beginning to bring it down to temp. Once it reaches the desired temp it runs roughly 65% of the time, or so they say.

Next up I want to go to two 6 volt.  If I go flooded I can get more amp hrs than agm  but I’ve read agm can be taken down farther and last longer so I’ll go that route.  Unless one of you convince me otherwise??


With My battery tray I installed new 250 lb sliders 5 years ago.  Even though that should be overkill after 5 years they are showing that they are getting tired with all the vibration and bouncing on our roads. So I installed a set of 500 lb slide rails and lowered the tray enough to allow the height needed for the taller 6 volt. 
The tray doesn’t allow enough length or width depending on how you set them for the larger 6 volt AGM.  I remove the riveted drawer catches , bent the front ledge down. Welded a couple of cracks in the side walls of the tray and cut the excess length so the door will close.  This now gives me more than enough room for the 6 volt.  The slots where the catches used to take hold work perfect for an adjustable heavy tarp strap that will keep the batteries in place and the tray from sliding against the door.

50% sounds about right.  5A x 18 hrs = 1080 wH, or 90aH of battery capacity.

Have you considered LiFePO4  instead? A pair of LiTime group 31 12v 140aH or 165aH batteries packs a lot of punch at 1/3 the weight for about the same price  and can be  safely discharged below 20% capacity.  If your converter can be configured for 14.2v charging, the only additional hardware needed is a dc-dc charger to protect the alternator.  If you might be adding solar at some point,  check out the dual input dc-dc chargers from Renogy that support charging from both the alternator or solar panels.  The difficult  part is figuring out the wiring since PC doesn’t provide diagrams. If you need help with that send me a pm. I made the switch last winter

Calcruiser.  I have looked at lifepo4. From what I’ve read I need to do something to protect the Alt and I have no idea if my converter on a 2011 can charge them. Next is cost, I have no idea of what the cost is to bring my rig up to speed for the lifepo4. 


Pm sent

Calcruiser.    I’ve sent two pm’s and although they say message sent when I check sent messages nothing current is showing.  Let me know if not received

 Got it 

Update on fridge conversion to 12 volt.  We recently took a short 4 day trip. At 5 pm the day before departure I turned the fridge on.  The following morning when loading the fridge was at 34 degrees and the freezer was at 4. Over the course of the 4 days the fridge maintained between 33.5 and 34.9 degrees. I never had to make any adjustments.  It’s as sim Poole as just turning on your fridge. Nothing to adjust.  The one con is while connected to shore power.  In the 2552 the charging unit is directly below the bed. The 12 volt systems causes the charger to kick on frequently. It’s an additional fan noise along side the inverters fans. This may or may not bother you.  Personally I wish I could throw a switch to turn the charger off at night.

Overall I wish I’d known of this sooner. I like it soooooo much better than the three way system.

One change I’ll make is If I find a way to shut the charger off at night it will be on my to do list.