Freezer Refrigerator 12 or 110 mode

[Disbus]

Originally Posted by Simplicity

I finally pulled the trigger and went for a 12v/11v Whytner 95qt, 3.18cuft, chest freezer.

It pulls 5.5A/12v and based on rough averages, will use about 44ah (based on 8 hours of compressor time per day).

It's taller than wide, but I'm okay with that as I will add an insulated horizontal door at the height of the compressor shelf and make that my frozen section, and keep the upper portion around 38 degrees.

It was $742 total, and only has a 1 year warranty. Amazing how Whytner wants to claim how great they are but only provide a 1 year warranty.

It's no where near the deal the OP got, but I did a lot of searching, and this I would consider a fair price.

Awesome. I think whynter makes a good product. They're local here in Southern California. I thought for sure I would be paying $600 until one day I saw the one I finally purchased. On to the next modification.

[Kentucky Dreaming]

I'm tickled with the Dometic 3 cubic foot, 3 way fridge in my truck camper. If I do decide to go the bus route, I will be bringing it with me. It sips propane when I boondock with my 2 old mutts. Gets even colder on shore power.

[rossvtaylor]

As Steve (Simplicity) mentioned, you lose some energy in the transition from 12V DC to 120V AC. So, generally, running in the native 12V (if the fridge is capable of that) is usually more efficient. One thing I didn't see mentioned in the comments yet, but is important to factor in, is the energy "cost" of running the inverter...not the conversion loss but the idle consumption of the inverter itself.

If you have a 3000W inverter running, with the plan to power your fridge with that, you need to check the idle consumption of the inverter and add that to your overall calculation. I recently did this for someone on a FB group and their inverter, at idle, would actually use more energy every day than the fridge itself. So this more than doubled the "energy cost" of running a 120V fridge vs a 12V DC fridge. If you leave this out of the calculations, you won't get a fair comparison.

Personally, when designing a system, I like to use two inverters instead of one big one. The primary always-on inverter (if you have one on all the time) should be as small as possible...just enough to power the things for which you need AC power all the time. Then turn on the bigger inverter when needed, to power the microwave or mini-split or whatever high draw items you have. Even better, have both inverters switched to turn them on as needed. If a big inverter uses 77W at idle, like the one I checked for the FB bus owner, that's about 6 amps just sitting there. Over a 24 hour period, that's 6x24=142 amp-hours...a ton of energy, just to keep the inverter on. I suggest that every bus owner get a clamp-on DC ammeter so they can measure these things.

[BeNimble]

Agree with you Ross..however..

Technically, a fridge can't run directly on 12v dc, the DC must be converted to AC to make a motor spin, which involves losses. 120v AC is already AC. In addition, higher voltage is always more efficient in general. Of course, a specific product can vary widely how it operates, which kind of motor it uses, what electronics it has, which chips it uses, etc, etc.

But in theory, a 120v AC is more efficient than 12v DC to run a motor.

In addition, there are inverters that are load sensing that have low idle consumption. In further addition, as I've discussed before, the most efficient fridges with inverter compressors adjust the speed of the compressor to avoid the inefficiency of a stop-start, and as such, they are always running so there is never any 'idle' of an inverter to power them.

[john61ct]

From a practical not theoretical POV

12/24Vdc fridges are designed to run natively off grid from battery stored DC power.

That is their most efficient mode.

Feeding them mains power for those so equipped, is less efficient, as there is an added rectifier/conversion step that adds losses. Of course mains is so cheap the lower efficiency doesn't really matter.

However, if DC power is what's available, then inserting an inverter to feed the fridge AC power will again increase inefficiency even further, and usually off grid battery stored energy is at a premium.

[BeNimble]

I would not be so sure all 12v fridges run on 12v natively, for those that also run on 120vac, if they don't come with an external 120vac->12v adapter, they could very well run on 120vac internally, and use an inverter from 12vdc.

As a practical matter, running a watt meter will give you the real answer for whatever fridge you have.

[Bus'n it]

Anyone have input on the Furrion Arctic 12v fridge? I love the style of it and the size is perfect. I can't find much reviews about it online.

[Rwnielsen]

I'm just going to bite the bullet and get a Norcold 12v compressor model around 10 cubic feet. Need solar first to run it

[john61ct]

Originally Posted by Bus'n it

Anyone have input on the Furrion Arctic 12v fridge? I love the style of it and the size is perfect. I can't find much reviews about it online.

Never came across it yet in dozens of forums over a decade.

Likely a marketing outfit slapping a label on units built by a large OEM

which latter determines the quality.

Use image search to see if you can spot the clone models

also learning what model compressor will narrow things down