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Discussion Starter · #1 ·
I had planned on a DC only Truckfridge TF130 which is said to draw around 50 watts I believe.

Does anyone use a residential AC only fridge in their van off an inverter? Is this feasible? Something like this unit:

https://www.samsclub.com/sams/3-2cf-fridge-dsv-in-club/prod18910244.ip?xid=plp:product:1:1

The only electrical info I see is 220Kwh per year and 0.8A draw. Is this doable with 200 watts of solar and 220ah of batteries? Really, with the savings you could get another solar panel, two more batteries and still saved hundreds of dollars.
 

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I run my fridge on ac, 24/7 summer. I have 300watt solar 300 amp battery. I lost the 12v cable and just too lazy to hard wire the 12v, so I just plug into the inverter.
 

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I had planned on a DC only Truckfridge TF130 which is said to draw around 50 watts I believe.

Does anyone use a residential AC only fridge in their van off an inverter? Is this feasible? Something like this unit:

https://www.samsclub.com/sams/3-2cf-fridge-dsv-in-club/prod18910244.ip?xid=plp:product:1:1

The only electrical info I see is 220Kwh per year and 0.8A draw. Is this doable with 200 watts of solar and 220ah of batteries? Really, with the savings you could get another solar panel, two more batteries and still saved hundreds of dollars.
I've always used a 110 vac dorm fridge in my vans but I just upgraded to the TF130. It's a great unit and I wish I did it 3 years ago when I built my Promaster. Yes, it is $650 more but now the only AC I have or need in my van is for the micro so I turn the inverter on for 5 or 6 minutes a day when I need it. I never had a problem with running a dorm fridge of my 2000w inverter and you sure can't beat the price of them but now I have no need to ever plug in anywhere and the TF130 is a sweet product, for sure.

Bottom line - if you can afford it, go for it and you won't regret it otherwise a dorm fridge will do the job for you with minimal if any problems.
 

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I run my fridge on ac, 24/7 summer. I have 300watt solar 300 amp battery. I lost the 12v cable and just too lazy to hard wire the 12v, so I just plug into the inverter.
But, I'm assuming it's actually a 12 VDC RV fridge that you are just running off a 110 VAC brick so not really a good comparison, sorta the middle road to take.
 

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2014, 138WB, High Roof, Gas, SW MT
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Hi,

220 KWH a year is 0.6 KWH or 600 watt-hours a day.
600 watt-hrs translates to (600 volt-amp-hrs) / (12 volts) = 50 amp-hrs per day, but running from a 90% efficient inverter would be 56 amp-hrs per day.

With the 120VAC fridge, you also have to have the inverter on all the time. My inverter uses about 10 watts when its on doing nothing -- about 20 amp-hrs a day if its just sitting there doing nothing. If the fridge actually runs about 5 hours a day (which is equivalent to 600 watt-hrs running on 120 VAC), the inverter idle time would be 19 hours, or about 16 amp-hrs of idle time wasted inverter power.

My Norcold NB751 used 42 amp-hrs per day when I tested it under pretty warm conditions.
http://www.buildagreenrv.com/design...alley/measuring-refrigerator-electricity-use/

So, bottom line --
About 40 amp-hrs a day for DC fridge
About 72 amp-hrs a day for your AC fridge (including inverter on standby wasted energy)


Have to say I'm a little surprised that the AC and DC fridges are this close. I think that when KOV measured power use on his AC and then DC fridges there was more difference. So, the numbers above may be optimistic.

For me our DC fridge at 40 amp-hrs a day is our largest load by a pretty good margin, and I'd just not want to nearly double that with an AC fridge. But, it does seem like it could work.

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Here is an interesting post in which the author says he got the daily consumption of his 120 VAC dorm fridge (219 KWH per year) down to 20 amp-hrs a day when run off a 12 volt battery and inverter. He uses quite a bit of external insulation. I'm a bit skeptical, but he seems to have done a fairly careful job.
http://www.sportsmobileforum.com/forums/f34/modified-energy-star-3-2-cu-refrigerator-15187.html

Wish I had room to add some external insulation to mine.

Gary
 

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Well, he keeps the fridge at 42°f! I run mine at 32°f. Why even bother at 42°?

I'm very suspicious about a lot of these claims!
 

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Discussion Starter · #7 ·
Hi,

220 KWH a year is 0.6 KWH or 600 watt-hours a day.
600 watt-hrs translates to (600 volt-amp-hrs) / (12 volts) = 50 amp-hrs per day, but running from a 90% efficient inverter would be 56 amp-hrs per day.

With the 120VAC fridge, you also have to have the inverter on all the time. My inverter uses about 10 watts when its on doing nothing -- about 20 amp-hrs a day if its just sitting there doing nothing. If the fridge actually runs about 5 hours a day (which is equivalent to 600 watt-hrs running on 120 VAC), the inverter idle time would be 19 hours, or about 16 amp-hrs of idle time wasted inverter power.

My Norcold NB751 used 42 amp-hrs per day when I tested it under pretty warm conditions.
http://www.buildagreenrv.com/design...alley/measuring-refrigerator-electricity-use/

So, bottom line --
About 40 amp-hrs a day for DC fridge
About 72 amp-hrs a day for your AC fridge (including inverter on standby wasted energy)


Have to say I'm a little surprised that the AC and DC fridges are this close. I think that when KOV measured power use on his AC and then DC fridges there was more difference. So, the numbers above may be optimistic.

For me our DC fridge at 40 amp-hrs a day is our largest load by a pretty good margin, and I'd just not want to nearly double that with an AC fridge. But, it does seem like it could work.

------------
Here is an interesting post in which the author says he got the daily consumption of his 120 VAC dorm fridge (219 KWH per year) down to 20 amp-hrs a day when run off a 12 volt battery and inverter. He uses quite a bit of external insulation. I'm a bit skeptical, but he seems to have done a fairly careful job.
http://www.sportsmobileforum.com/forums/f34/modified-energy-star-3-2-cu-refrigerator-15187.html

Wish I had room to add some external insulation to mine.

Gary
GReat post thanks a lot. So if im a bit conservative and assume that the AC fridge option will be about doubt the amp hours, or 80 amp hours, I should be ok.

Gotta say im pretty tempted. At the price of these AC fridges I dont care if it only lasts a couple years. If the TruckFridge didnt last much longer then that id probably shed a tear.

I mean, I could get the AC fridge, another 100w panel and two more 6v batteries and still save $320 over the TF. That would give me around 440Ah of batteries, 220 at 50% and 300w of solar. I think thats might be the way to go for me.
 

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Somewhere in between those temperatures is a better number. Our house fridge is set for 40 but items trapped in the back will freeze if we go much lower.
These tests are always subject to the whims of the tester but I have some faith in KOV’s results that a similar size cheap’o dorm fridge running on an inverter will use about twice as much power as a proper 12 volt RV unit. It might not make much difference to Winston as his inverter is on all the time for other stuff. Most of us would use the extra 40 Amp-Hours for better things. A margarita blender for instance!
 

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In the end if you only pay $60-$80 and trash it in 3 years it's no big deal. I'd give you mine for free just to see it go if you were in NH! ;)
 
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