I was thinking I need a spare dometic power board. As I was looking up part numbers I saw a picture of a three way relay. So two part question. I have a Dometic RM 2662.
1. What board is recommend?
2. Can I convert from two way to three?
3. Is it worth the effort?
Glen
"1. What board is recommend?"
Others may chime in but I think conventional wisdom would recommend a Dinosaur board. ;)
I put a dinosaur board in my Lance camper (same fridge). The tech people at the company were helpful, shipping was fast, cost reasonable, and it fixed the problem. As I installed it, I hit a little problem. I called them and they walked me right through to the easy and effective solution.
Harold
Glen, I had a Dinosaur board installed as a replacement for the Dometic board in my 2003; it was a Micro P-711. You can check the Dinosaur website to verify if this is the same board used as a replacement in your much newer LD! ;)
MICRO P-711 page (https://www.dinosaurelectronics.com/MICRO_P-711.htm)
I also had the water heater board replaced with a Dinosaur; all the specs needed for model fit for replacement boards for water heaters and refrigerators are on the Dinosaur site. And, as Harold said, the 'Dinosaur people' also very helpful with tech support.
I was thinking I need a spare dometic power board. As I was looking up part numbers I saw a picture of a three way relay. So two part question. I have a Dometic RM 2662.
1. What board is recommend?
2. Can I convert from two way to three?
3. Is it worth the effort?
Glen
Unless you're traveling to a really remote place for an extended period of time, I'm not sure that having a spare board is needed. You can order and ship stuff around the US pretty quickly these days and being without a fridge isn't as big of a problem as an engine that won't start.
Dinosaur boards are available on Amazon with prime shipping.
A three way fridge has extra parts and pieces beyond just the control board. You can probably upgrade (a guess on my part) but it will involve more than just a board swap. I doubt that would be worth the effort.
Rich
'03 MB in NC
I was thinking I need a spare dometic power board. As I was looking up part numbers I saw a picture of a three way relay. So two part question. I have a Dometic RM 2662.
1. What board is recommend?
2. Can I convert from two way to three?
As suggested, get the Dino Board and keep the original as spare. If doing so, consider getting a board for the water heater, I have replaced many more heater boards than refrigerator boards.
A three-way refrigerator has a 12-volt heating element in the chimney . Our LD's RM2662 does not have the opening in the chimney for the heater.
I have no idea if the chimney can be made to work with a 12-volt element. If possible, the refrigerator most likely needs to be removed to perform the work, a fun job in itself. look around for someone with a 3-w
When the 12-volt heater is operating, it draws around 25-amps, needing large wires (10-gauge minimum) to supply to supply the power.
A system needs to devised to automatically switch to another power source when the engine is not running.
A 25-amp draw can seriously draw the coach battery down if accidentally left on for several hours, after the engine is shut off.
Installing an inverter for running the refrigerator on electric, while traveling, may be a better choice.
While searching, I found a company that sell a compressor cooling system that replaces the propane system, it fits some Dometic and Norcold models. Interesting idea.
Products | JC Refrigeration (https://jc-refrigeration.com/products/)
https://www.youtube.com/watch?v=Yte1V3CkDrw
Larry
Larry, I recently purchased a replacement cooling unit for my M3662 from JC Refrigeration and was very tempted to get the compressor unit. In the end I got the propane unit since I'll be doing a good amount of boondocking. Some day when I have more solar capacity I would really like to give the compressor type a try.
As suggested, get the Dino Board and keep the original as spare. If doing so, consider getting a board for the water heater, I have replaced many more heater boards than refrigerator boards.
A three-way refrigerator has a 12-volt heating element in the chimney . Our LD's RM2662 does not have the opening in the chimney for the heater.
I have no idea if the chimney can be made to work with a 12-volt element. If possible, the refrigerator most likely needs to be removed to perform the work, a fun job in itself. look around for someone with a 3-w
When the 12-volt heater is operating, it draws around 25-amps, needing large wires (10-gauge minimum) to supply to supply the power.
A system needs to devised to automatically switch to another power source when the engine is not running.
A 25-amp draw can seriously draw the coach battery down if accidentally left on for several hours, after the engine is shut off.
Installing an inverter for running the refrigerator on electric, while traveling, may be a better choice.
While searching, I found a company that sell a compressor cooling system that replaces the propane system, it fits some Dometic and Norcold models. Interesting idea.
Products | JC Refrigeration (https://jc-refrigeration.com/products/)
https://www.youtube.com/watch?v=Yte1V3CkDrw
Larry
This is an awesome upgrade. I can't wait to get this project going on my RV.
This is an awesome upgrade. I can't wait to get this project going on my RV.
Looking again the JC Refrigeration compressor replacements, they are all 120-VAC , needing a inverter to operate.
Products | JC Refrigeration (https://jc-refrigeration.com/products/)
Using 120-VAC compressor is a way to lower the cost of construction, 120-VAC compressor are widely available, 12-volts compressor are more of a specialty item and cost more.
While a compressor refrigerator might be a good upgrade, if you spend the money to beef up the solar and battery capacity, I would want a 12-volt compressor and not have the added cost and inefficiency of converting solar to 12-volts, storing it in the battery and then using a inverter to convert it to 120-VAC, to operate the refrigerator.
A lot of stuff to go wrong, especially considering the Dometics are relatively trouble free and not dependent on sunshine or generator runs when boon docking . When it comes to keeping food cold and safe, the most dependable system should win the contest .
A conversion kit may work great and then it may not, depending on the engineering of the unit and how it's installed. A performance test by an independent lab would be great to see, I'm not holding my breath waiting.
A compressor refrigerator built from the ground up as a compressor refrigerator may be a better to go for peak efficiency and for getting a fresh body, rather than converting an old Dometic, with brittle plastic.
Still trying to figure out how they determined the compressor was 8 times more efficient.
Larry
Still trying to figure out how they determined the compressor was 8 times more efficient.
Larry
Don't know. Your magic 8-ball doesn't do numbers well. :D
"Looking again the JC Refrigeration compressor replacements, they are all 120-VAC..."
No, they offer a choice between 120 VAC and 12 VDC versions. (For some reason, they don't offer an AC/DC model--a significant drawback.) But instead, I'd consider a Vitrifrigo DP2600 (https://www.suremarineservice.com/Galley/Refrigerators-with-Internal-Compressors/DP2600IBD4-F-2.html). As I recall, that model will fit nicely into the space of a 6.6 cubic foot Dometic absorption fridge, and will give you 8.1 cu. ft., a big increase in capacity.
Yes, it will cost more than just replacing the cooling unit. (The cost of a DP2600 is roughly comparable to the cost of a new absorption fridge like the ones LD uses.) But you get a whole new fridge, with substantially more capacity, and it runs on either AC or DC (with automatic switchover). And swapping fridges will be a less complicated than what's shown in the video.
My own approach in both my LD and Airstream was to buy a Vitrifrigo DP150, a smaller 5.3 cu. ft. model. The 20% smaller capacity was adequate for my needs, the power consumption is lower, and the smaller physical size allowed me to add plenty of extra insulation, reducing power consumption still further. (Also, I was able to add an 8" high storage compartment below the fridge. :-) But I realize that's not for everyone.
"Looking again the JC Refrigeration compressor replacements, they are all 120-VAC..."
No, they offer a choice between 120 VAC and 12 VDC versions. (For some reason, they don't offer an AC/DC model--a significant drawback.) But instead, I'd consider a Vitrifrigo DP2600 (https://www.suremarineservice.com/Galley/Refrigerators-with-Internal-Compressors/DP2600IBD4-F-2.html).
Miss that, didn't see it on the products page. The lack of a dual voltage option is a definite drawback and another reason to buy a refrigerator designed from the start to use a compressor .
The Vitrifrigo lDP2600 looks like a good choice for a compressor replacement, being smaller overall than the Dometic, while having more capacity is a nice upgrade and it allows for extra insulation around the perimeter. Added insulation is a proven way of reducing the power consumption.
The big issue is having an adequate source of 12-volt power. With your experience with long-term boon docking, now without a generator, what would you consider to be the minimum amount of solar wattage to cover your mid-winter needs, running a compressor refrigerator and normal living needs?
I'm guessing it needs to be, at a minimum, in the 600-800 watt range, mate more depending on one's electronic needs.
This is important information for those considering the change, is there enough acreage on the roof for the number of panels needed and still provide enough foot room for access cleaning and maintenance?
The battery capacity also needs to be upgraded, the fastest and easiest (not the cheapest) way to do this is with lithiums, replacing the lead-acid or AGMs.
Before lithium batteries, adding two more batteries, for a total of four, was a very common upgrade.
Our 23.5' FL has room for 500-watts of panel, without making access difficult. Longer models may accommodate more panels, depending on the location of the antennas, vents and A/C.
For those thinking about this, making an accurate drawing or map the roof will help determine how many panels can be placed, panels come in a range of dimension, mix and match to maximize wattage.
Solar keeps getting cheaper, Home Depot sell 100-watt panels for $80.
https://www.homedepot.com/p/Grape-Solar-100-Watt-Polycrystalline-Solar-Panel-for-RV-s-Boats-and-12-Volt-Systems-GS-Star-100W/204211365
Larry
"With your experience with long-term boon docking, now without a generator, what would you consider to be the minimum amount of solar wattage to cover your mid-winter needs, running a compressor refrigerator and normal living needs?"
Good question, Larry, and one that I should have addressed. Although an efficient 12 V compressor fridge (not a residential type!) may only draw 5 to 8 amps when running, that's a lot more than a propane-powered fridge, and it does mean you need adequate solar and battery capacity if you're planning on boondocking.
"Adequate" depends on where you're camping. I spend winters in the desert, where there is usually plenty of sunshine. I have 600 watts on the roof (not tilted--it isn't practical with my Airstream) and in the colder months I set out another 200 watts of tilted panels on the ground. I had a similar setup on my midbath Lazy Daze, but there I could tilt the roof panels. Although a nuisance to do, it definitely helped in the wintertime.
The 600 + optional 200 watt setup works well for me. I have 320 Ah of LiFePO4 batteries, which charge faster and can be safely discharged deeper than AGM or flooded-cell batteries. They get me through cloudy/rainy periods, which seldom last more than a few days.
But if I were camping regularly in wooded areas, or in areas such as the Pacific Northwest that have extended cloudy periods, I would probably not install a 12 V fridge. It's just too hard to get enough solar power under those conditions. On the other hand, if I were vacation-camping mainly in the summer, and doing it in places with lots of sunshine, I might be able to get by with 400 watts.
All of this assumes that I'd get by on solar power alone, rather than running a generator to add power when the sun isn't available. When I started traveling in my midbath, I used the generator quite a lot, but over the years I pretty much stopped, because I hate the noise and vibration. (Not to mention the maintenance.) And I didn't buy a generator for my Airstream. I get by year round without one... but again, I mostly camp in the southwest, and I have lots of solar panels.
Yes, "it depends"... but if you have an idea of when and where you're going to camp and how often you're willing to use your generator (if at all), hopefully the above will help you decide whether a compressor refrigerator fits your lifestyle.
P.S--Did I mention that unlike absorption fridges, they don't catch fire? :-)
Don’t even think of converting a two way fridge to a three way. Too much to change even if you could. Better to add an inverter and run it on AC.
I have a three way RM2663. It overheats on DC, dunno why yet. I’m told that the DC element does not have enough watts to keep the boiling process going. When it doesn’t boil the cooling process stops and the boiler overheats. Doesn’t really make sense to me even tho I understand the theory.
Overheating would be caused by all the ammonia leaving the boiler and not returning. The remaining water at 300 psi will overheat. Why doesn’t the ammonia return if the heater lacks power? Dunno.