Refrigerators: residential vs. RV

[ewacowboy]

Originally Posted by MRUSA14

Ewacowboy, I find your figure does not match my experience. My refrigerator uses much less power than that. Don't forget that the fridge cycles on and off and is not running constantly.

As an exercise, I looked up the power usage of a 19.5 cuft Samsung refrigerator here. It shows estimated annual power consumption of 445 KWH. Divide that by 365 days per year and you get 1.22 KWH per 24 hours. 1.22KWH is 100 Amp Hours @12.2 volts. Add 10% for inverter inefficiencies and you will take about 110 amp hours out of your batteries in 24 hours. This means 25% of the capacity of 4-six volt batteries used in 24 hours.

If the above calculation is correct a residential fridge will last about 4 times as long as you calculated on a battery charge. If it is wrong, somebody please show me where it is wrong.

As I'm sure your calculations are correct, I was using the real time experience from the link I posted as my research. In the article/video they show that they used 400 amp hours in 11 hours with the residential they were using without any solar or shore power and nothing else but parasitic draws in the rest of the coach.

[vsheetz]

Originally Posted by ewacowboy

In research I found that a "standard" residential fridge will deplete a battery bank of 4-6 volt batteries in about 11 hours (down to 50% charge). To me that was not acceptable.[/url]

Does not align with my experience, and not others methinks. I can go several days on battery with only the RR active without getting down to 50℅ SOC. I have six 6v GC2 batteries.

[txaggie79]

Well, when our RV fridge died, we went with a residential. DW is very happy with her ice cream being actually frozen, I'm happy that DW is happy. DW made this a no brainer for me.

[Dranoel]

My RR experience seems to agree with MRUSA's calculation, but for a larger fridge. We have a 25 cf Whirlpool that uses 6 amps/hr, 7 if I leave the ice-maker on.

[LarryW21]

I'm pleased with the RV-type fridg...in camp, on the road etc. With only 240 amps in my two T-125s, a residential fridge would limit me too much since I perfer federal and state campgrounds.

[vsheetz]

Originally Posted by paz

The only upside to an RV refrigerator I see is it is a little better suited to dry camping because it will run on propane. However, the drawback of a residential refrigerator not being able to run on propane can easily be easily be overcome by adding an inverter and a couple of additional batteries. Adding a couple of batteries isn't that big a deal considering what is in my opinion the far superior performance of a residential refrigerator - better cooling, hard ice cream, cold beer, lots of ice cubes, less food spoilage, and up to 50% more interior capacity for essentially the same exterior dimensions.

Agree.

[nothermark]

The problem always comes back to where to put the batteries and how to handle the weight. Not much of an issue in a larger DP but a big one in a C or most gas A's.

[Triangle Drifter]

Like lots of choices, it depends.

Most of us use CGs that have power most of the time. Many won't go anywhere unless there are FHUs waiting for them. Very few don't want to be near anyone else & dry camp virtually exclusively.

Then there those of us who like to occasionally rough it in comfort. For us which fridge is a bit of a question. The nice big multi door RV fridge is great till it has to be replaced. By the time the RV tech waves goodbye you are near $5000 poorer.

That kind of money buys a larger fridge, in the same dimensions, plus a pure sine wave inverter & a serious upgrade in the battery bank department.

We installed the inverter & upped the battery bank capacity some time ago to make life comphy at music festival dry camping etc. Replaced the RV fridge with another already. Ouch! Next time it will be a residential. Done the research for size already.

[select55]

Originally Posted by LarryW21

I'm pleased with the RV-type fridg...in camp, on the road etc. With only 240 amps in my two T-125s, a residential fridge would limit me too much since I perfer federal and state campgrounds.

totally agree. I don't boondock and wanted a larger fridge. IF a larger more efficient LPG fridge at a reasonable price was out there I would have gone that route but alas there is no such animal in this world
only having two six volters will require way too much gen time if using a RF and boondocking

BUT RF do not use a huge amount of power especially if the ice maker is off when used on the inverter

[wa8yxm]

Absorption cooling (Standard RV unit) uses 12 volt to run the on-board computer and control things, Modern ones use either 120 vac or propane to power the cooling cycle, this technology has been around a long time, it is reliable save when a joint breaks or a pipe fails. It is not all that efficient but you have lots of propane compared to battery.. If you are "OFF THE GRID" this is by far the best choice.. Oh, they need defrosting from time to time (mine does now)Page 2.

Residential units: Often offer a bit more "Inside" but eat electricity, generally NOT as much as a RV unit on 120v but way way way more than an RV unit on propane (Gas) If you find yourself "off the grid" for more than a few hours not driving your batteries may not love you any more. Also, believe it or not, many contain HEATERS Yup HEATERS, that's to self-defrost...

Advanced high effiency Compressor Units..... (Danfoss or Sling)

these units eat only electricity.. It seems strange to have the phrase it this way but WITH THE DOOR CLOSED.. 30-45 watts Less than 4 amps at 12 volt DC (Open the door, the light can easily draw 2 amps).

If, like me, you are comfortable with Propane.. I'd go with the traditional RV unit.

If not.. The High Effiency compressor ones, both Dometic and Norcold have or had offerings in this area... I have a chest freezer (Engel) of this type.. Very pleased with it.

[select55]

If you find yourself "off the grid" for more than a few hours not driving your batteries may not love you any more. Also,

my 4 six volt batterys that are 6 years old went from 2;30 PM to 6AM next day and were still at 12.3 volts running the 18cft residential fridge
through the 3000 watt inverter