Compressor Fridge Info Thread, for those of us considering switching

[HMD1056]

It seems the compressor type refrigerator is becoming quite popular in RVs. Is it possible that Oliver will begin offering this option? If a compressor fridge can be retro fit, it seems that Oliver would have little trouble offering the option from the get-go. Perhaps the external vent could either remain or have a fiberglass cover option.

[Overland]

I've had a couple of conversations with Oliver about that. For a while they were considering using a compressor fridge in the Elite I, since they're smaller and easier to get through the door, but in the end they found another unit that would work. My guess is that at the moment, they're worried that the battery capacity isn't enough. I definitely think that supplemental solar is needed.

[HMD1056]

It's a shame they don't offer the option for those who order the solar option on either model. For those who will use shore power only as needed, wouldn't the 4 AGM batteries be sufficient? I do understand that LP has its place in an RV, but it seems to me that the more appliances that can be run using solar power to keep batteries charged, the better ecologically and economically. Thank you so much for your response.

[BackofBeyond]

Nice job Ken.

Really like the result - wondered how long you were going to put up with the problematic original unit. I will definitely want to look at the final product - seems like the perfect replacement. Please keep us updated on the results.

 

For those of us with the full solar - Oliver should seriously think about this option - it is one I will consider should my OEM unit start acting up. It has , from time to time, shut itself off - when on propane - I keep an eye on it - but.... I have an ARB portable Danfoss compressor unit we use in conjunction, never a problem, uses little power, bulletproof.

 

RB

[BackofBeyond]

Ken,

Are fans in circuit with the t-stat of the unit, - what turns them on/off - temp sensor?

RB

[mountainoliver]

The fridge has a circuit specifically for a fan. The fans turn on and off with the compressor. They start a second or so before the compressor starts and turn off at the same time as the compressor.

[mountainoliver]

An incremental update. I finished the upper and lower grills so I’d call the installation complete. The fridge has been running continuously on either DC or AC since I received it coming up on a month now. We have been on a long weekend camping/test trip and we’re pleased with it’s performance. It maintains upper teens to low 20’s in the freezer and low to mid 30’s in the fridge regardless of the outside temperature. The compressor seems to run for about 5 minutes and then is off for about 5 minutes if it’s hot (95 or so) outside and is off a bit longer if it’s cool (mid to upper 60’s) outside. So far the 320 watts solar and four T105 batteries have been able to keep up. Testing will continue on upcoming trips.

[Overland]

Great work on the vents. Looks like it came that way from the factory.

[mountainoliver]

Thanks! I originally really hoped to find something already made but there just doesn’t seem to be grills that are 2 or 2 1/2 inches wide and 24 3/4 inches long out there.

[ScubaRx]

I know a guy in Virginia that makes these vents up in any size if anybody needs one.

[Twospirit]

As I get closer to owning an Ollie I’m envisioning how I will use the trailer. I currently own a Norcold Portable Refrigerator having a DanFoss Compressor 12V or 110V adapter. DanFoss compressors are superb in their performance and low power consumption (aH). Having multiple fuel options LP, 12V, and 110V covers all bases when boon-docking especially in high altitude areas and in colder seasonal temps.

[BackofBeyond]

We also have a portable, from a prior rig, an ARB ac/dc, that we use for liquids and fruits/vegies (in the upper chamber). It does an excellent job, and is extremely efficient. This really frees up room in the Dometic fridge. Now we have used the Ollie a good deal this year, about 12 weeks worth, and I have rarely been pleased with the Dometic, mainly in hot weather. I maintain a temp sensor to monitor temps, and in 90 degree + weather it struggles if you open the door any at all. It also takes 24 36 hours to get to temp from start up - esp. if you load it with room temp stuff. The ARB is much better - the Danfoss compressors just kick butt.

 

AND - the Dometic is sketchy on propane - it has shut itself off 5-6 times, I do a visual check every time I look at the thing, and glance at the temp monitor. Never did it while on voltage.

 

If it ever gets regularly repetitive - I'll be copying Ken's install.

 

[Mirna]

Greetings:

 

Compression refrigeration is a very interesting topic and something we will consider for our Oliver in the future (we recently placed our order). However, as the researcher in our team, I came across Eutectic Plates. Has anyone in this forum used them? Thank you for your feedback.

 

General link to eutectic plates: https://www.google.com/search?q=eutectic+plates+refrigeration&rlz=1C1CHBF_enUS720US720&oq=eutectic+plates&aqs=chrome.3.69i57j0l7.8773j0j1&sourceid=chrome&ie=UTF-8

 

[SeaDawg]

Mirna, many of us who have (or had) sailboats are familiar with eutectic plates, but they're usually called cold plate or holding plate systems.

 

We've used holding plate refrigeration on our boat for 40 years, on the 2nd set now.

On the boat, they're like big blocks of metal, filled with coils of solution. The plates are attached to the side of our heavily insulated icebox bins. A compressor runs off the engine, cooling the solution in the plates when the engine runs. The solution absorbs heat during the day, keeping food at a fairly consistent safe temp if we run the engine an hour or two a day. With good insulation in the box, it's very efficient.

There are newer systems out that can chill the plates with a danfoss compressor when we don't want to run the engine. Our newer plates can use both types of compressor.

 

Recommendations we've received are to cool the box initially with the big engine driven compressor. Use the 24v danfoss to maintain, and then maintain the batteries with solar.

The 12v danfoss compressor Isotherm that Overland bought has the option of adding a small holding plate, (ASU). I don't remember if he opted for it, or not. I kind of think he did.

 

Holding plate technology is proven, efficient, and highly dependent on great insulation. It's also kind of bulky, heavy, and can be tough to get cold enough when air cooled in hot weather. Many boats use keel cooling ( water cooled) systems to transfer waste heat, like frigoboat.

That said, if you plug in every night to cool the plates, like some refrigerated trucks, it could be a great solution.

 

I don't know of any holding plate systems designed for rvs, other than the assistance of the isotherm asu. Doesn't mean they don't exist...I just haven't seen any.

That said,along those lines, I keep a freezer pack or two in our dc fridge. If I have room, I freeze it during the day when I have good solar production. If not, just the cold pack and thermal mass of the beer probably helps keep the fridge cooler...?

 

Sherry

[The Shackelfords]

Attached is a pretty cool video of a guy who converted his 3 way refrigerator to a high efficiency DC compressor style fridge. He got the conversion kit from a company called JC refrigeration out of Indiana. They build custom retrofit kits for dometic rv refrigerators. I believe in the video he said the DC compressor runs on 60 watts of electricity while running and most importantly was able to keep his existing refrigerator. 

 

[Overland]

Pretty cool.  Depending on what they cost, that may be a nice solution.

[SeaDawg]

In my case, we installed the Truckfridge tf130, still indel fridge,  danfoss/ secop compressor.  I picked up almost a half cubic ft of extra storage. Plus an interior (led) light. We love it, despite the Barbie sized freezer.

I've looked at reviews from owners on irv2 and other websites. And, I  flew through the amish refrigerator website. It doesn't talk about danfoss/secop compressor technology, but at some point, i saw draw of 4 or 5 amps running on dc, so... must be some kind of swing arm compressor. 

If I  had to do it again, I'd still replace our old Dometic with the truckfridge.  I picked up extra fridge space,  although I now have a shoe box freezer. 🥴 Plus, I gained room for a drawer beneath. Without the heater behind,  the replacement fridge can be slightly bigger. The danfoss/secop takes up much less space than the threeway ammonia/heater unit. The novakool a few people have installed gives even more fridge and freezer space, but I was looking at budget. And what would fit through my door, in an older Elite,  without having to remove trim or shower wall. Basically,  something we could do ourselves.

Most reviews I read about jc/amish refrigerators were from big motorhomes,  where they had the choice of removing the windshield to replace the fridge, or retrofit the old. In their case, I'd definitely retrofit. I know friends of ours, with an older class a, replaced the cooling unit in a 3way to avoid just such a hassle. 

I didn't find a unit to retrofit a dometic rm2454, but I  could have flipped through too quickly. Possibly,  it's there, but I  think their focus is on bigger rvs, at least right now.

Sherry 

 

[Ray and Susan Huff]

On 6/16/2018 at 10:06 AM, Overland said:

I think you’ll be fine with 200, but of course it depends on how much you consume otherwise. I mentioned above that we added a National Luna 60 liter fridge freezer to the truck for extra storage. It uses the same danfoss compressor and I run it off a single lifeline battery and a 200 watt portable panel. Over our three week trip I never saw the battery dip below 80% but we were lucky and saw very few cloudy days. I have the option to charge the battery via the alternator but I disconnected that after a few days since the panels worked so well.

 

Speaking of heat and fridge ventilation, I just went and checked the fridge in the truck. It’s 97 here and the truck has been parked in the sun all day so it’s baking in there. The fridge is indeed struggling a bit but still reads 43 degrees. The freezer is at 8. Not surprising since it’s probably 120 inside the truck.

Novel idea . . . . fridge in the truck. . . . . would come in handy at other times, as well.

[Overland]

It’s in our kitchen now, on pandemic duty. 

[SeaDawg]

A number of people have asked me,,via pm, about dc fridges, in the last month, for conversions. Thought I'd just bring up this old thread, for those thinking about it.

I'll add this link, as well.

 

 

[C&MCurrie]

I have recently completed the conversion with the Isotherm that Oliver uses. Not too bad, hardest part was disassembling Norcold 4.1 and then reassembling it after removal from my smaller Oliver Elite. Had to remove refrigerator door and cooling unit in order to fit through the Oliver door. The Isotherm Cruise 130 fits through narrow passageway after removing its door. BTW, The Norcold works fine after reassembly and currently trying to sell. 

[MAX Burner]

47 minutes ago, C&MCurrie said:

I have recently completed the conversion with the Isotherm that Oliver uses.

Very clean looking install/mod!  Thanks for posting...

[SeaDawg]

@C&MCurrie, nicw install.

What material did you use on the upper fridge vent? We lined the old vent with two layers of heavy visquene,  and added a sheet of Styrofoam insulation, eventually.  (Started with just visquene. )

 

Did you get the lower vent unit/table from Oliver, or what did you use. Very nice! We always have a small table in that space, anyway. Super nice to have one that just rides on the Ollie!

Big kudos!

[C&MCurrie]

Thanks!  I used white 1/4” thick plexiglass from Amazon and the table was ordered directly from Oliver. The rear wall of refrigerator cabinet, from bottom to top vent, was covered with 1” insulating foam board purchased at HomeDepot. 

[dewdev]

3 hours ago, C&MCurrie said:

Thanks!  I used white 1/4” thick plexiglass from Amazon and the table was ordered directly from Oliver. The rear wall of refrigerator cabinet, from bottom to top vent, was covered with 1” insulating foam board purchased at HomeDepot. 

Curious - If the Norcold is working fine, why did you replace it?

i.e. What were the extra benefits that the Isotherm provided over the Norcold?