12 volt compressor refrigerators

[Salty]

I've been looking at the 12 volt refrigerators. Saw This one:
https://www.recpro.com/rv-refrigerator- ... ess-steel/
This refrigerator is larger - 10 Cu/ft - so there would be surgery involved.
in my trailer, the wiring for 12VDC operation is all there, since originally the refrigerator was a 3 way.
So, just thinking out loud, broad strokes, what would need to be done?
Remove the top vent and patch the hole.
Patch the refrigerator cover.
remove the command center shelf and command center.
Reinforce the floor
new shelf
new wiring strip above
new wiring terminal block below
Then again, the dometic/norcold 8 cu/ft models would likely just slide in. Hole patching and wiring adjustment would still need to be done, but to a lesser degree. The high amperage wire for the original 3 way in plumbed in down below, just a fuse (5 amp slo-blo?) holder and +12vdc wiring to it would be required.

[Razorback]

I guess it boils down to your own preferences and reasons. If our Avion was stationary or semi-stationary I might consider a 110V/compressor fridge. But for our purposes, the 2 or 3-way RV fridge is our choice. Ours is a Norcold N831 if I remember correctly. It works great, especially with the inside and outside fan modifications I have done.

Seems like a LOT of modifications are needed for that swap, though.

[Salty]

Agreed, for a 10cu/ft refrigerator, yeah. Had I not already relocated my command center, I wouldn't dream of it.
As for an 8 Cu/ft refrigerator, it's about a snap. For an Avion that originally came with a 3 way refrigerator, the wiring is already there. You have a pair of 8 gauge wires ( ground and +12VDC) down low behind the refrigerator. Capping the roof requires a piece of aluminum 17" x 23". If you are coating your roof, then no need for anodized aluminum, as you're going to coat it in ReRubber or Kool Seal anyway. The inside of the roof vent is easily covered by bending down the existing sheet metal used in creating the interior opening. Some spray foam in the void and you're insulated on top.
Down low, at the lower access panel, another 17" x23" piece of aluminum to block off the inside opening, a piece of 1" foam board in the void and you're insulated. The outer refrigerator access door is a bit trickier in that there is an existing frame to remove and the blocking panel isn't a simple rectangle, but an oval as you well know.
Here's another way to look at it. If you remove your refrigerator and take a good hard look at the paneling on either side, you may find it's a bit weathered - or more than a bit weathered. On Mine, I had already used Smith & Co wood epoxy to correct, but a recent check showed the panel delaminating. Sealing off the roof and rear access will stop this weathering process.
Yes, it is a project. Yes, the 12 VDC refrigerators are a bit expensive. As for conversion to a residential refrigerator, Razorback makes a good point: If you are stationary. I've looked at some of the manuals for residential refrigerators and they will say explicitly "not for use in an RV" which means they won't warranty a failure and they likely don't travel well.

[KYAvion]

I did a small residential fridge in my prior trailer and it actually worked out really well. I just left the ventilation door and vent on the roof in place to allow for airflow, and I sealed everything up around the front of the fridge. The access panel also allowed me to bolt the fridge down from behind. The fridge cooled down really fast and held that temp without running much at all. I also hooked up a cheap inverter so I could power it going down the road. The fridge didn’t cost much (less than $200), so I figured if I ever had issues on the road it would be cheap to swap it out for a new one. The only thing I didn’t care for was using bungees to ensure the doors stayed closed, but I bet you could find a better solution.

[Markinalaska]

I’ve also been looking into a 12 volt only refrigerator. I’m leaning towards the Nova Cool 9000dc. But so far I haven’t found a place that has any in stock. It costs about the same as a dometic 7cf two way but has 9.1cf of space instead of 7 and it will slide right into the hole my old fridge was in. I also like that the nova cool has a bottom freezer. I’m currently running a small 110v fridge but am planning on hitting the road next year and want a built in instead of trying to figure out how to hold my current one in place and not be able to fly open while on the road. I’m looking at the dc only version since when I’m on ac power the 12 volt will be supplied by the converter and once off the converter it will continue as if it is. This particular unit uses the danfoss compressor which is very efficient. I think it draws around 3 amps when the compressor is running. I’m also looking at adding 350 watts of flexible solar on the roof to help offset the battery draw of the fridge while not on ac. I will also upgrade my batteries to give be at least 200 Ah of power. Maybe lithium but more than likely a pair of good 6volt batteries. People have said good things about that type of setup and most never have to run a genset to keep the batteries up. The main issue I see with anything larger than the 9.1 is that the curvature of the wall behind the fridge makes the height that’s actually available to use is about what the old one fit. Once you get into the cabinet above the fridge it isn’t 24” anymore. Good luck with whatever way you decide to go.

[silverloaf]

Nova Cool 9000dc looks like a very nice fridge. I did an on-line search and found it is available as AC/DC as well as DC only.

Due to a boom in RV-ing (possibly COVID-driven last year), there are huge supply chain shortages on RV accessories like this.

[Rostam]

I did a small residential fridge in my prior trailer and it actually worked out really well. I just left the ventilation door and vent on the roof in place to allow for airflow, and I sealed everything up around the front of the fridge. The access panel also allowed me to bolt the fridge down from behind. The fridge cooled down really fast and held that temp without running much at all. I also hooked up a cheap inverter so I could power it going down the road. The fridge didn’t cost much (less than $200), so I figured if I ever had issues on the road it would be cheap to swap it out for a new one. The only thing I didn’t care for was using bungees to ensure the doors stayed closed, but I bet you could find a better solution.



EBE0BE99-8AD4-4F0D-A454-68CB26AE80D2.jpeg

KYAvion,

Question: how do you switch between 110V and 12V? (When you have shore power vs when you are towing and relying on inverter output?). Do you have to manually plug the fridge into inverter outlet every time?

Thanks!

[KYAvion]

[/quote]

KYAvion,

Question: how do you switch between 110V and 12V? (When you have shore power vs when you are towing and relying on inverter output?). Do you have to manually plug the fridge into inverter outlet every time?

Thanks!
[/quote]

That’s right. However, the amp draw was so insignificant that I didn’t need to worry about it, and I didn’t except for when parked more permanently at home. It’s been long enough ago that I don’t recall the exact amp draw, but again it was so insignificant that it could have run off the inverter all the time and it would have been fine.

[Rostam]

Thanks KYAvion. Any chance you have a link to the inverter you got?

[KYAvion]

I sure don’t. It was just an old one my father had laying around. I’ll see if I can find it and will take a pic of it.