Experiences with running fridge off main car battery overnight for a few nights in a row?

[plh]

Nice set up. You got a write up on that battery box? I have a marine batt box now with deep cycle group 27 (I think). Big and heavy. Was fine in the truck but I'd like to shrink it for the Outback. Will probably go to a Yeti 400 Lithium with a solar panel.

Did Yeti fix the 12V output on these yet? Thought I read somewhere that they were a 3s pack and therefore the usable voltage for a fridge doesn't match up well. 11.1 nominal voltage, 12.6 fully charged, but more likely 12.3. A 4s pack (14.8 nominal) is more suitable for a fridge. Low voltage shutoff on a lot of fridges is 11.5, so you won't get a lot of run time from that Yeti.

 

[DaveM]

Did Yeti fix the 12V output on these yet? Thought I read somewhere that they were a 3s pack and therefore the usable voltage for a fridge doesn't match up well. 11.1 nominal voltage, 12.6 fully charged, but more likely 12.3. A 4s pack (14.8 nominal) is more suitable for a fridge. Low voltage shutoff on a lot of fridges is 11.5, so you won't get a lot of run time from that Yeti.

The low voltage shut off on the 35 qt Doemtic is listed at 10.1v, so should be ok. Yeti has released an upgraded port as well that bypasses the low volt limits on the batteries and supplies higher voltage for fridges: https://www.goalzero.com/shop/yeti-accessories/yeti-lithium-12v-regulated-cable/

 

[BritKLR]

Long before all the dual battery setups I ran my Engel 45 off a single battery for years. Battery size and capacity of course matters, but generally speaking at night, once everything cools down the fridge shouldn't run that much so you should be fine. Have fun!

 

[plh]

The low voltage **** off on the 35 qt Doemtic is listed at 10.1v, so should be ok. Yeti has released an upgraded port as well that bypasses the low volt limits on the batteries and supplies higher voltage for fridges: https://www.goalzero.com/shop/yeti-accessories/yeti-lithium-12v-regulated-cable/

That cable does not fit the 400 Lithium

 

[DaveM]

That cable does not fit the 400 Lithium

Confirmed, bummer. Goal Zero seems to be telling customers they are incorporating the fix into updated models but no indication those are out yet. My Dometic says it's low volt cut off is 10.1 so I don't think I'd need the cord anyway. What is the difference in running via the AC plugs? I think I read you get full power but the draw may be higher so less time from the batt overall? Either way, I just did a test load up and I'm thinking about heading to REI tomorrow to pick up the Yeti 400. It's 40 pounds lighter than my marine batt and probably about 1/3 smaller in size!

 

[plh]

Confirmed, bummer. Goal Zero seems to be telling customers they are incorporating the fix into updated models but no indication those are out yet. My Dometic says it's low volt cut off is 10.1 so I don't think I'd need the cord anyway. What is the difference in running via the AC plugs? I think I read you get full power but the draw may be higher so less time from the batt overall? Either way, I just did a test load up and I'm thinking about heading to REI tomorrow to pick up the Yeti 400. It's 40 pounds lighter than my marine batt and probably about 1/3 smaller in size!

Sounds great, can't wait for a report. I have no real idea how the Yeti will preform. I have my own DIY 4S 2000 watt Li-ion pack that I use for my Edgestar.

 

[DaveM]

Quick test shows the Dometic will run off the Yeti 400 at the Low voltage cutoff setting. I think it drew about 2.9 amps for a second or two then settled into 2.4 amps with compressor on. Battery was about 50% here according to the readout (not the batt image though). Will pair with a solar panel eventually. Will take notes from the drive out to Sedona and report back.

 

[Martinjmpr]

You didn't say but will you be staying in a hotel or home? If so the easy solution is to just take the fridge inside and plug it in. Another option (if there is a 110v AC outlet) is bring a long extension cord and run the extension cord to the car at night.

I don't know if there is an 'always on' 12v power outlet mod for the Subaru. I know there was on my old 4runner and it worked great. All I had to do was make a 3" long jumper with blade connectors on either end and plug it into a couple of specific terminals on the back of the fuse block.

 

[DaveM]

You didn't say but will you be staying in a hotel or home? If so the easy solution is to just take the fridge inside and plug it in. Another option (if there is a 110v AC outlet) is bring a long extension cord and run the extension cord to the car at night.

I don't know if there is an 'always on' 12v power outlet mod for the Subaru. I know there was on my old 4runner and it worked great. All I had to do was make a 3" long jumper with blade connectors on either end and plug it into a couple of specific terminals on the back of the fuse block.

We're staying in a home in Sedona so that's not an issue, but on the way out and back we'll be stoping a few times at hotels. The 12v plugs in the OB are not always-on but could be modified. I just got the Yeti 400 lithium instead and it seems to work fine with the Dometic. Should be enough to keep it running for at least two nights if I'm plugging it back into the car during the day when driving.

 

[bglenden]

My (new) Dometic CFX 65W does not run with my (2 year old) Goal Zero 400 Lithium. I have the fridge on the low voltage setting. At about 75% remaining on the battery the compressor will only run for a few seconds and then shut off, not maintaining temperature. My theory is that the starting surge momentarily drops the voltage too low. Obviously I can run from the 120V AC inverter socket, but the minimum power draw there is about 10W, vs <1 from the 12V socket. This is pretty annoying.

(Also annoying is that the Dometic plug is not compatible with the Goal Zero socket, but I had a 1 plug to 3 socket adapter lying around that works, although I hate having an extra connection).

I have an email in to Dometic and Goal Zero, but suspect I'll have to buy a new battery.

 

[DaveM]

My (new) Dometic CFX 65W does not run with my (2 year old) Goal Zero 400 Lithium. I have the fridge on the low voltage setting. At about 75% remaining on the battery the compressor will only run for a few seconds and then shut off, not maintaining temperature. My theory is that the starting surge momentarily drops the voltage too low. Obviously I can run from the 120V AC inverter socket, but the minimum power draw there is about 10W, vs <1 from the 12V socket. This is pretty annoying.

(Also annoying is that the Dometic plug is not compatible with the Goal Zero socket, but I had a 1 plug to 3 socket adapter lying around that works, although I hate having an extra connection).

I have an email in to Dometic and Goal Zero, but suspect I'll have to buy a new battery.

The 12v plug wouldn't work? Mine works fine, but my fridge is the older model. Wonder if there's any drop off due to the adapter? Might be worth splicing in a new plug on the fridge. I was running ok at 50% power on the new Yeti 400. Hope it works all the way to full discharge or I'm out $600!

 

[john61ct]

DC-DC voltage converters / stabilizers are cheap as chips at such low currents,

can't trust cheap-Chinese current ratings, but get one rated at least 20A or 150W, should be plenty, might need a heat sink, place in the fridge ventilation path.

 

[bglenden]

Nope, my new Dometic 12V plug does not work with my older 12V Goal Zero socket, and stops running the refrigerator at about 75% charge remaining.

I could use a DC/DC charger I guess, but I already have a lossy method that works (using the 120V AC plug/socket), but maybe it would be better (one conversion vs. two).

 

[DaveM]

Update on the performance of the Dometic 35 qt with Yeti 400 Lithium, Redwood City CA to Sedona AZ:

Sunday PM to Monday AM (14.25 hours @ 40*): 96% @ 5:50pm > 72% @ 8:10am

Monday PM to Tuesday AM (14.5 hours @40*): 70% @ 5:30pm > 47% @ 8:05m

Ambient temps both nights probably ranged from 80* initially to 60* by morning. Fridge was set to 40* both nights on low cut off setting. Tuesday morning the fridge was off due to low voltage cut off. The yeti showed 47% 10.9 volts. Doemtic says the low voltage limit is 10.1 volts, so not sure why it shut off. Turning on the Dometic emergency override should have turned the fridge back on full, but nothing happened, so not sure it was actually the fridge that cut off. I plugged in the 110 plug to the Yeti and the fridge came back on showing 47* (indicating it had only just turned off early that morning). The fridge went from 47* to 39* after running on 110 fro maybe 1-2 hours.

Not sure what to make of all that yet, still processing. Basically I got almost two nights of running time in warm night temps on a single full charge (no charging up during trip). Not what I’d hoped for. I plan to buy the 12v charge plug for the fridge to keep it topped off in transit between stops. That will help a little. Eventually I’ll add the solar panel. If the the solar (50 or 100 watts) can keep up with demand enough in camp to give me 3 - 4 days all batt at least that will take care of most of our trips

 

[dreadlocks]

10.9v is resting volts, but under load its hitting 10.1v