RV 12v fridge

[Kip in Ga.]

Although it still works, I am getting g a bit concerned that our 18 Year old Fridge is nearing its last days. Replacements are very expensive considering the fridge and labor.
A really nice 12v fridge with Danfoss compressor seems to run 1/2 to 2/3 the price of a new 3 way fridge. Plus the cost of labor. I figure I can install the 12v myself.

So wanting to hear from folks that have done it and what brand
and style.
2002 Casita 17 SD. Fridge is the larger. 4 cubic foot, I think.

Thanks ,
Kip

[CarlD]

I'm happy with my truckfridge 4.6 cuft. I built my trailer interior and installed the fridge new. I would buy another one if I had to.

[Kip in Ga.]

In these Casitas the cabinets and furniture are all built-in fiberglass. The space for the fridge is 23.5w x 35ish high and 28 deep. Fridge will have to pass thru a floor to ceiling 18.5" opening.

Ive read good things concerning Truck Fridge brands, will check and see if one will pass through the opening and fit into the space.

Thanks.
k

[gordon2]

In addition to TruckFridge, look at Indel B, Nova Kool, or any with a Danfoss (now Secop) compressor. They are more alike than different (for same size food storage). The difference is usually more about insulation and the overall quality of the box rather than the compressor. And if it works on 120 VAC as well as 12 VDC.

[Kip in Ga.]

I just checked Truck Fridge web site. Looks like the TF130 would do the trick. But they are backordered. Will check some other webs.

[Kip in Ga.]

Originally Posted by gordon2

In addition to TruckFridge, look at Indel B, Nova Kool, or any with a Danfoss (now Secop) compressor. They are more alike than different (for same size food storage). The difference is usually more about insulation and the overall quality of the box rather than the compressor. And if it works on 120 VAC as well as 12 VDC.

Will do!
Thanks
k

[CarlD]

I don't understand why one would spend the extra money to purchase one of these fridges that is both 12 Vdc and 120 Vac. The only time you would need the ac operation is if your 120 Vac to 12 Vdc charger has failed. Maybe I'm missing something.

[Glenn Baglo]

I don't know why anybody would buy a 3-way fridge, when 12V DC and propane cover all the bases.

I considered it, until it was explained to me that if I left a campsite after a couple days running my furnace and some lights, my battery would be depleted. And, if I travelled with the fridge on 12V, I would arrive at my next camp with a still depleted battery, because the power from the vehicle is not enough to both charge the trailer battery and run a 12V fridge.

I opted for 120V AC and propane. I travel with the fridge on propane.

[patrick crawford]

i installed a norcold 12v/120vac in my 16' casita (small fridge). works great for me.

p@

[gordon2]

Originally Posted by CarlD

I don't understand why one would spend the extra money to purchase one of these fridges that is both 12 Vdc and 120 Vac. The only time you would need the ac operation is if your 120 Vac to 12 Vdc charger has failed. Maybe I'm missing something.

For a built-in unit I would agree.. I was thinking more of or portable unit like my Indel B, which I can use in the camper on 12 volts or bring in the house to use as a supplemental freezer or or beer cooler, on 120 VAC. If you can get by with a smaller amount of food then the portable has advantages (esp if top opening) and I might suggest getting that instead of using a larger built-in unit. But if you want 4 cubic feet of food storage than built-in is the way to go and 12 volt operation only would be OK.

[gordon2]

Originally Posted by Kip in Ga.

..
So wanting to hear from folks that have done it and what brand
and style.
2002 Casita 17 SD. Fridge is the larger. 4 cubic foot, I think.

Thanks ,
Kip

Please see this:
https://www.truckcamperadventure.com...329J5TlnD3dVCQ

If you plan to boondock pay attention to the power use info along with solar system sizing. I ran some tests and my power use was generally consistent with what is in the article. I think his comments about solar are dead on correct (for him and most small camper owners).

By the way, Glenn's comments seem to be describing an absorption fridge. It would not be too hard to keep a trailer battery charged with a charge line from the tow vehicle AND run a Danfoss type fridge while traveling.

[thunderworks]

Originally Posted by Glenn Baglo

I don't know why anybody would buy a 3-way fridge, when 12V DC and propane cover all the bases.

I considered it, until it was explained to me that if I left a campsite after a couple days running my furnace and some lights, my battery would be depleted. And, if I travelled with the fridge on 12V, I would arrive at my next camp with a still depleted battery, because the power from the vehicle is not enough to both charge the trailer battery and run a 12V fridge.

I opted for 120V AC and propane. I travel with the fridge on propane.

I'm no expert, but I believe that the 12v compressor fridge units require far less power than the propane/DC combo absorption units, and consequently, do not excessively drain a car battery while driving.

[CASITA BANANA]

I have an Engel 12/120v compressor fridge that's been running off my solar for a year. It's nice to have the worry of it getting too cold rather than it running at 50* plus on a hot day like my old Dometic 3-way. And it was a couple hundred less than a new Dometic.

[CarlD]

I have a lithium 100 ah battery and charge the trailer at around 8-9 amps while driving. More than enough to recharge the battery and run the fridge. The fridge draws less than 4 amps when running and only runs about 1/2 the time. It draws around 1/4 the current that an, hundred year old technology, absorption fridges draw. If you camp where it is sunny 100-200 watts of solar is adequate to run the trailer.

[Timber Wolf]

I have the larger Truckfridge, 130 I believe and like it a lot. I do have a couple of points though. It draws more power than I expected. In fairness this is probably because my daughter and I are going in and out of it a lot. Also, I can’t for the life of me figure how they can design a refrigerator with a freezer that won’t hold a quart of ice cream. Makes good ice though.

If I had a do over I would still install a Truckfridge but would go with a smaller one supplemented with a really good cooler or chest type 12v portable. Many of the chest type can be turned down for use as a freezer. And a chest type would not experience the “cold dump” the front-door type have every time you reach in for a Dr. Pepper or Dew. Also, the chest type could run off and be in the TV for day jaunts. I have heard of folks building a sliding tray in their RV and using the chest type fridge that way. Might be the best of both worlds.

[SherryNPaul]

We installed a truckfridge 130 a few years ago. We really love it.
It cools down very quickly (usually less than an hour), and stays cold.
There are caveats, explained in the truckcamper link above. Though it uses far, far less than a 3 way in dc, it still uses roughly 2 to 4 ah per hour .
We have 200 watts fixed solar, a 100 watt portable panel, and 2 group 27 agm batteries.
Everything is great if we're travel camping. Highway sun is awesome for charging batteries. If you're camped in partial to full shade, you'll need to break out portable solar, especially in shoulder season, and have a reliable readout to know your status.
We insulated around the cavity with Styrofoam board. Sealed off the exterior vents with plastic sheeting, as no longer needed.
My truckfridge has an indel badge on the front. It comes in black, only. One door swing, only.
It's quiet, no exterior lights to annoy me during the night, and works flawlessly. And, it has an interior light, so you can actually see the content of the fridge when you open the door.
Downsides: power consumption, compared to 3way on gas. The shoebox sized freezer. The door is not superinsulated, and sweats.
It fit through the door of my 2008 Oliver, and through the narrow space between cupboard and shower corner, with a strong 1/8 on each side. We did the install ourselves. Gained a short height drawer beneath, and maybe a half cubic foot of fridge compared to the old dometic .

I'm willing to do the monitoring, and deal with the portable solar/sometimes generator to keep batteries in prime shape in rainy, or overcast strings of days. It's a tradeoff , but one you need to be aware of.
I'd probably never go back to 3way/absorption, because I have been so happy with our results. But, everything is a balance .

[SherryNPaul]

I should add, my caveats are for those like me, who almost never gave hookups. If you're weekend campers, or usually plug in anyway, don't even worry about the power consumption. The Danfoss compressor is great.

[patrick crawford]

there's a 100w solar panel on the roof of my casita wired permanently to it's controller. a days driving while running the fridge (if the sun's out) gets me to the end of the day with fully charged batteries. there's another 100w panel mounted on the truck's topper. that panel powers a go sun 12v/120v cooler in the bed of the truck. that cooler is another device that uses the "magic" compressor for low power consumption. the go sun runs on a lithium battery pack that also arrive at the end of the day fully charged. in the event of bad weather i can still make it thru a day's driving (the cooler will run 14 hours on a full charge). and yes, it's a great beer cooler. it's been running non stop on 120vac since the pandemic started (9 months or so).

to compensate for potential inclement weather i keep a honda 2000i mounted on the trailer's tongue. that generator has a permanent plug & connecting wiring. why, i can even run it while going down the road altho, the only time i've done it was to make sure it would.

p@

[redbarron55]

Not all electric compressor fridges are Danfoss (Secop) rotary. Engles and Norcold often (always?) use swing compressors that are basically solenoids that bounce back and forth to compress the working fluid. These might be noisier, but have no starting surge that the Danfoss has.
I installed the Norcold 704DE when I rebuilt my Scamp and recently swapped out for a newer Norcold 490DE that is quieter, but smaller.
I find that the new unit draws less current if the battery voltage is higher and draws a little more as it drops.
The new power supply in the Norcold uses inverter technology to operate the compressor changing the 120VAC to ~24 VDC for the compressor and the 12 - 24 volt to the same level. In this unit the changeover is basically seamless and designed into the unit with no relays or switches involved.
Here is a link to how the swing compressor works for the curious:
https://www.sawafuji.co.jp/en/technology/swing_motor/

[Raspy]

JD,

The oscillating compressor runs on AC. It may have a frequency other than the common 60 cycles/sec because it would need to match the natural oscillation frequency of the mass of the piston and spring assembly in the compressor, to minimize the work. It's a brilliantly simple concept and would require an inverter, which it has. This makes it especially suitable for trailers, boats and trucks.

So, I think it actually converts DC power to AC at a frequency best suited to its operation. Not the other way around of converting AC to DC.

I used to have a Norcold reciprocating hermetic compressor system that ran on AC it made from the 12 volt DC input on my boat. One of the reasons for that conversion was to avoid brushes in the motor, which are not serviceable in a hermetic system. It was also fine with 60 cycle household current, because it was not an oscillating compressor.

Am I missing something with the conversion?