Dump the RM8551 ?

[Vermilye]

Mine can be tilted to either side or to the rear. I prefer the rear since side tilting puts a lot of surface area that wind pushes against the narrow side of the mounts. No photos of the side to side tilt...

[LarryandLiz]

I’m in a similar plight as Myron with our Dometic RM8551 and wondering about switching it out to a NOVAKOOL R3800. I see that Tworainy put a R3800 into their 2014 17b last July 2020, has road tested the new unit and reports good results.

This is our current set-up: 2014 17b with 160 solar watt and the 2 Six Volt batteries (original supplied by ETI). I just purchased an additional GoPower 130W portable unit (for extended camping when we are in the shade @ Cultus Prov Park once a year with the kids/grandkids) The rest of the time we boondock.

? Would the 160W roof and 130w solar be enough ...
? I think we should probably replace the batteries since they could be getting to be about 5 years old
? We’re in Maple Ridge and discovered that NOVAKOOL doesn’t sell direct ... I’ll have to find a dealer here

Thanks for any comments I appreciate this Forum

Larry

[MyronL]

Tworainy, if you're listening, tell us what you use to power your R3800 Novakool when in transit. Solar, batteries, DC to DC charger ??

[John in Santa Cruz]

Originally Posted by MyronL

Tworainy, if you're listening, tell us what you use to power your R3800 Novakool when in transit. Solar, batteries, DC to DC charger ??

Most tow vehicles should easily be able to power a compressor fridge, it's only about 8 or 10 amps part of the time.

[MyronL]

I found this on line quote interesting:

"...Although the Danfoss DC compressor is much more efficient running on 12 volt power than the ammonia absorption type, it still consumes a considerable amount of amperage during a 24 hour day. The consumption rate is typically 60 amp hours a day, which breaks down to 2.5 amps or 30 watts per hour...

...What this means is that your RV will require a minimum of two 12 volt batteries (about 200 amp hours) and a effective way to keep them charged, either a 200 watt solar power system or a generator..."

[Ian and Sue]

Originally Posted by Vermilye

Mine can be tilted to either side or to the rear. I prefer the rear since side tilting puts a lot of surface area that wind pushes against the narrow side of the mounts. No photos of the side to side tilt...

So do you just pop out two hinge pins and add in the prop rods and pin them in place on the two ends of the separated hinge? Simple, safe and functional.

[MyronL]

Here's what I made for my portable 100watt panel.

[Vermilye]

Originally Posted by Ian and Sue

So do you just pop out two hinge pins and add in the prop rods and pin them in place on the two ends of the separated hinge? Simple, safe and functional.

Side tilt - remove pins, add bars & replace pins. Rear tilt - remove bracket bolt, add shorter bars, replace bolt. Takes about 20 minutes & two rounds of the trailer with my 6' folding ladder. I generally only tilt them if I'm staying more than a couple of days...

[Tworainy]

We simply turn our Nova Kool R3800 fridge on, runs on DC, cools super-quickly (like 2-3 hours!), then leave it on. It's always cool.
As for cooling while in transit, we still leave it on (no propane, so runs on DC) and the 2x6V batteries charge without any degradation.
Our solar set-up is a 180W portable unit from Princess Auto, which includes the controller (super easy to use).
Seemed to do the job last summer.

[Davin]

Originally Posted by Patandlinda

Hold on there Ross still have the RmD 8551 ! Many mods ,the most important insulating the cavity . Still working ! Will not trash until it is unfixable . And the shelves are SS not plastic . We deal with horrible temps in the summer as you know so we are still good and we monitor the refrigerator temps and bring a cooler of course ,just a habit for over 40 years . Pat

Patandlinda, can you provide detail of what you did to insulate the cavity? Any photos? Thanks!

[rubicon327]

Originally Posted by Davin

Patandlinda, can you provide detail of what you did to insulate the cavity? Any photos? Thanks!

Not Patandlinda but I know that they added a few photos to my original Refrigerator Test thread. Direct link:
https://www.escapeforum.org/forums/f...tml#post255309

[MyronL]

Now wondering how to minimize the tipping points of the cash commitments involved versus raw desire to take action while in confinement.

My 100ah lithium battery just became a mitigating factor. If I dump the R8551 and replace it with the wonderful NovaKool ($1050 +shipping) that requires 200 amp hours of battery - must I spring for another Lithium ($1000) to get to that needed 200ah or, do I dump the Lithium ---replace it with two Costco lead acid batteries (est. $250) to get the 200 amp hours for a NovaKool?

Sure not wanting to double the cost of the change-out.

Could I then sell my lovely but pricey Battleborn outright to recoup some of the NovaKool investment? Then, what do I do with the otherwise functional RM8551? Would not put these on Craigslist because I don't like that site, too risky...IMO.

[John in Santa Cruz]

Originally Posted by MyronL

...My 100ah lithium battery just became a mitigating factor. If I dump the R8551 and replace it with the wonderful NovaKool ($1050 +shipping) that requires 200 amp hours of battery - must I spring for another Lithium ($1000) to get to that needed 200ah or, do I dump the Lithium ---replace it with two Costco lead acid batteries (est. $250) to get the 200 amp hours for a NovaKool?
....

lead acid batteries really should only be 50% discharged, so a 220AH combined pair of GC batts is good for 110AH actual per cycle. a lithiium cell can be discharged to 80% or more each full cycle, so 100AH is good for 80AH, or 2 100AH is good for 160AH.


IMHO, if it ain't broke, don't fix it.

[Tworainy]

Mega bonus I forgot to mention earlier about the Nova Kool fridges: your trailer doesn't need to be level. In fact, they say it will work at angles up to 30 degrees. Helps when you're traveling from place to place.
That said, if Tamago was parked at 30 degrees, I figure it would be rolling down the street!

[gbaglo]

Dometic doesn't need to be level either. If you are travelling, the fluid doesn't stay in one place and if you a sleeping and roll out of bed, you need to level anyway. If you are comfortable, so is the fridge.

[rubicon327]

Originally Posted by MyronL

Now wondering how to minimize the tipping points of the cash commitments involved versus raw desire to take action while in confinement.

My 100ah lithium battery just became a mitigating factor. If I dump the R8551 and replace it with the wonderful NovaKool ($1050 +shipping) that requires 200 amp hours of battery - must I spring for another Lithium ($1000) to get to that needed 200ah or, do I dump the Lithium ---replace it with two Costco lead acid batteries (est. $250) to get the 200 amp hours for a NovaKool?

Sure not wanting to double the cost of the change-out.

Could I then sell my lovely but pricey Battleborn outright to recoup some of the NovaKool investment? Then, what do I do with the otherwise functional RM8551? Would not put these on Craigslist because I don't like that site, too risky...IMO.

This thread feels like we are going down a rabbit hole. Personally I think you have a big commitment ahead of you to get off propane for the fridge AND be happy with the outcome. DC compressor fridge, more battery, more solar, DC-to-DC charger....

[NEWYORKHILLBILLY]

I am no expert ,But from what a gather on the forum the RM8551 Has not preformed as well as the current modes EFT is installing . My current unit is Dometic DM2683 Why not just replace this with a another propane/AC fridge that has a better track record? My unit has had no problem in temps 90's. freezes ice fast and keeps every thing cold. In fact this thing works better than my unit in the casita. The casita unit would have to be turn down as it got cold outside. The unit i set on level 3 and it seems to stay the same temp weather it 20 degrees or 90 degrees. I have not used it anywhere its over 94 degrees so i cant say what it would do at 100 degress..

[Rossue]

Hey Billy! Good you're fridge bee-haves; Gen 1 doors are narrower and fridge options are very limited. If my RMD8555 died I can't buy another one because Dometic discontinued them. It isn't bad actually, yet the 8551 is well documented here as a problem.

[Lawrence A]

Originally Posted by Tworainy

We have the Nova Kool R3800, though we did consider the R4500, as both seem to require the same cavity opening, but the R3800 uses half the power, an important consideration when boon docking.

To complete installation, we had to add a small filler piece above the fridge, not a big deal.

As for power needs, we use a portable folding 180W solar system from Princess Auto that easily plugs into the tow vehicle plug. Kinda snazzy, but really easy!!

This past summer, we had great success with this new setup, including the fridge's freezer making ice, and actually cooling, a first for us over the past few years!! We'd do this again.

Nova Kool was also the best priced compressor we could find. Having it locally manufactured was a huge bonus!

Tworainy, I'm curious about your solar panel from Princess Auto. I see it has its own built-in controller. I have a fixed panel on the roof of my 17B which of course has its own controller. You didn't say if you have a fixed panel as well as the portable and I'm wondering if the two controllers would be compatible. I suspect they will be due to the feed from the portable being thru the trailer plug but wondering if you (or anyone else) have any thoughts on the matter.

Apologies to everyone for being off-topic (fridges), but hey, the subject came up and I'd really like to know the answer to my question as I've been thinking I need to boost my solar capacity. Come to think of it, the answer might be of interest to others wanting to boost 12V power to a fridge so maybe it isn't totally off-topic after all.

[rubicon327]

Originally Posted by NEWYORKHILLBILLY

I am no expert ,But from what a gather on the forum the RM8551 Has not preformed as well as the current modes EFT is installing . My current unit is Dometic DM2683 Why not just replace this with a another propane/AC fridge that has a better track record? My unit has had no problem in temps 90's. freezes ice fast and keeps every thing cold. In fact this thing works better than my unit in the casita. The casita unit would have to be turn down as it got cold outside. The unit i set on level 3 and it seems to stay the same temp weather it 20 degrees or 90 degrees. I have not used it anywhere its over 94 degrees so i cant say what it would do at 100 degress..

From my research the limitation of absorption fridges is generally a 55-60F differential (outside ambient to inside fridge temp). If someone has better data please share. So at 100F if everything is working perfectly you can maintain 40F +/-. Unfortunately many installations are not meeting manufacturers requirements and/or there are fridge design/operational issues and the fridge can’t cool well. The RM8551 has clearly been problematic. There are a lot of fridges out there that do fine in mild weather but then fall on their face when the outside temperature gets too high (80F seems to be a common threshold). If you are cooling well at 94F on a setting of “3” don’t touch anything! Your fridge is doing really well.