Questions for those that switched from Norcold to residential

[Longshhm]

We are looking at switching to a residential fridge in our 2021 Reflection 295RL. The Dometic 8 cubic ft. unit it is garbage; it won't maintain temperatures and gets into the upper 40's during the day. It's at the dealer now for testing, less than 60 days after taking delivery. GD has opened a file on it, and I've talked with Dometic, but I don't expect much relief from that direction.
Our previous TT had a 10 cubic ft. compressor fridge with a dedicated Xantrax inverter; the fridge ran on the inverter only - it did not switch to shore power. Turn off the inverter and the fridge turned off, even when hooked to shore power. We had two Size 24 deep cycle batteries. Never had a minute's problem with it. That said, we never boondocked either. When traveling, the tow vehicle kept the batteries charged, and when hooked to shore power, the converter kept the batteries charged.
I was thinking about installing a similar set-up in our 5'er. We are looking at a Frigidaire 11.6 cubic ft. unit that has almost the exact footprint as our current fridge. I'm comfortable with DIY'ing the dedicated inverter and wiring, but I'm not as sure about what's needed to disconnect the absorption unit. I know I will need to cap the LP line ( not a problem), but I'm a little shaky on disconnecting it from the 12v system and making sure I don't create a problem elsewhere. Any advice, pointers, commentary, etc. would be greatly appreciated. After cruising these forums, it's obvious that there's a wealth of knowledge here. Please share. Thanks.

[Second Chance]

We are looking at switching to a residential fridge in our 2021 Reflection 295RL. The Dometic 8 cubic ft. unit it is garbage; it won't maintain temperatures and gets into the upper 40's during the day. It's at the dealer now for testing, less than 60 days after taking delivery. GD has opened a file on it, and I've talked with Dometic, but I don't expect much relief from that direction.
Our previous TT had a 10 cubic ft. compressor fridge with a dedicated Xantrax inverter; the fridge ran on the inverter only - it did not switch to shore power. Turn off the inverter and the fridge turned off, even when hooked to shore power. We had two Size 24 deep cycle batteries. Never had a minute's problem with it. That said, we never boondocked either. When traveling, the tow vehicle kept the batteries charged, and when hooked to shore power, the converter kept the batteries charged.
I was thinking about installing a similar set-up in our 5'er. We are looking at a Frigidaire 11.6 cubic ft. unit that has almost the exact footprint as our current fridge. I'm comfortable with DIY'ing the dedicated inverter and wiring, but I'm not as sure about what's needed to disconnect the absorption unit. I know I will need to cap the LP line ( not a problem), but I'm a little shaky on disconnecting it from the 12v system and making sure I don't create a problem elsewhere. Any advice, pointers, commentary, etc. would be greatly appreciated. After cruising these forums, it's obvious that there's a wealth of knowledge here. Please share. Thanks.

Nothing is needed to disconnect the absorption unit - turn off propane and cap that line, disconnect the 12 volt control power and unplug the 120 VAC power to the heating element. If you need to remove the cooling unit from the back to get the fridge out the door, the whole cooling unit unbolts from the back of the fridge in one piece. It's probably not necessary, though, if you take the doors off the front.

Now... you know that you loose energy using an inverter to make 120 VAC from 12 VDC batteries, right? Consider bypassing the the inverter altogether and going with something like this, instead:

https://www.recpro.com/rv-refrigerat...ainless-steel/

Rob

[Longshhm]

I had briefly looked at those, both this one and the Everchill. Dometic, Norcold and Furrion also make them, though Dometic is making their own compressors for them. I think the others are using the Danfoss compressors; the Danfoss is proven technology - I'm not so sure about the Dometic design/engineering.
That said, I'm assuming these would just be wired to the 12v fuse block that is already there for the absorption fridge? And that is tied to the converter?

[Longshhm]

Oh, and yes, I was aware that the inverter is, at best, 90-95% efficient, and current efficiency is dependent upon wire sizes and lengths.

[Second Chance]

I had briefly looked at those, both this one and the Everchill. Dometic, Norcold and Furrion also make them, though Dometic is making their own compressors for them. I think the others are using the Danfoss compressors; the Danfoss is proven technology - I'm not so sure about the Dometic design/engineering.
That said, I'm assuming these would just be wired to the 12v fuse block that is already there for the absorption fridge? And that is tied to the converter?

My guess is that you'd have to run a separate wire with a higher-rated fuse. The amperage for the 12 volt control board on the absorption fridges is very low. I think the fridge linked above says 7 amps for startup and one amp running. That's a lot more than a circuit board for controls needs.

Rob

[Longshhm]

You're right about that. I visited several websites to look at tech specs and manuals. Only Furrion provided access to a manual with installation instructions. They provided a table of recommended wire sizes, and the smallest recommended was 14awg for 5' or less. I'll probably need to farm out that part of the installation to someone with DC experience. With starting and running amperage like that, it would fit our needs well. The closest we come to boondocking is an occasional overnight stay in transit, and a small generator would top off batteries if needed. Thank you for the help.
Mike

[Second Chance]

You're right about that. I visited several websites to look at tech specs and manuals. Only Furrion provided access to a manual with installation instructions. They provided a table of recommended wire sizes, and the smallest recommended was 14awg for 5' or less. I'll probably need to farm out that part of the installation to someone with DC experience. With starting and running amperage like that, it would fit our needs well. The closest we come to boondocking is an occasional overnight stay in transit, and a small generator would top off batteries if needed. Thank you for the help.
Mike

Forum hint: use "Reply With Quote" (as I have here) and everyone will know to whom or what you are responding.

Rob

[Longshhm]

Forum hint: use "Reply With Quote" (as I have here) and everyone will know to whom or what you are responding.

Rob

Yessir. I'm new to this, so I appreciate any guidance. As a former work colleague would say, "Have a good 'un!"

[Longshhm]

Nothing is needed to disconnect the absorption unit - turn off propane and cap that line, disconnect the 12 volt control power and unplug the 120 VAC power to the heating element. If you need to remove the cooling unit from the back to get the fridge out the door, the whole cooling unit unbolts from the back of the fridge in one piece. It's probably not necessary, though, if you take the doors off the front.

Now... you know that you loose energy using an inverter to make 120 VAC from 12 VDC batteries, right? Consider bypassing the the inverter altogether and going with something like this, instead:

https://www.recpro.com/rv-refrigerat...ainless-steel/

Rob

Rob,
I revisited this and your commentaries. After continued frustration with our absorption fridge, there is no longer any doubt about replacing it. I do have a question about the 12v fridge you sent the link to - you said to bypass the inverter altogether, and I understsnd that there would be no need for an inverter on a 12v fridge, but, did you mean D.C. wiring directly from the battery bank to the fridge (with an appropriate breaker/fuse in the wiring)? I'm new to this, so any help is appreciated.

[Second Chance]

Rob,
I revisited this and your commentaries. After continued frustration with our absorption fridge, there is no longer any doubt about replacing it. I do have a question about the 12v fridge you sent the link to - you said to bypass the inverter altogether, and I understsnd that there would be no need for an inverter on a 12v fridge, but, did you mean D.C. wiring directly from the battery bank to the fridge (with an appropriate breaker/fuse in the wiring)? I'm new to this, so any help is appreciated.

No - I was merely commenting that using a 12 volt DC compressor fridge would negate the need for the inverter needed to run a 120 VAC compressor fridge off batteries. You would need to find out the amp draw on the 12V fridge and see what would be required to operate it. My guess is that the light gauge 12V wiring for the controls on the RV absorption fridge might not be up to the task - you may end up doing what you've outlined above.

Rob