Spillover, or separate fridge/freezer

[Typhoon]

Originally Posted by Richard Kollmann

Point of interest Adler Barbour CU 100 and CU 200 Systems both use Danfoss BD50 compressors. The Btu output of both CU systems are the same.

Hi Richard.

Seems like all the new Adler Barbour/Dometic machines are BD50 based. I do remember them using both , I actually had a BD35 based A/B unit in one of my boats.

Regards John.

[SV THIRD DAY]

Originally Posted by ColdEh Marine

Hi Richard.

Seems like all the new Adler Barbour/Dometic machines are BD50 based. I do remember them using both , I actually had a BD35 based A/B unit in one of my boats.

Regards John.

Yes
The only difference between the CU100 and CU200 is the worthless....ah I mean...added on water cooling option to the CU200....

(Toss flash-bang into room and head to Taco Cart)

[Typhoon]

Originally Posted by OzePete

Good advice John, I put the OP's freezer details through our Heat load / duty cycle estimator and using a single BD35 it would struggle as you indicated. Applying the two BD35 units, each to a single freezer plate, would provide adequate refrigeration for the freezer even in thee tropics. And like you said add the spare unit to refrigerate the fridge space as a a separate issue.
Heat load estimator for this cabinet assuming using just one BD35 indicates greater than 50% duty cycle.. not good.
Heat load Estimator | Ozefridge

Cheers Ozepete Ozefridge | 12 Volt Refrigeration Systems

Sorry , you are correct Pete. I was thinking of one of our BD35 based systems which will do a R30 insulated 7 or 8 cubic foot refrigerated box no problem , consuming between 10 and 15 amp hrs a day .

Regards John.

[Typhoon]

Originally Posted by SV THIRD DAY

Yes
The only difference between the CU100 and CU200 is the worthless....ah I mean...added on water cooling option to the CU200....

(Toss flash-bang into room and head to Taco Cart)

I agree , what were they thinking ?! The one I had was air only , Tossed that too.

Regards John

[Typhoon]

Originally Posted by Hoghead

It seems that the compressor model will determine spillover or not; and how many plates I need and where they are located.
I am now leaning toward 2 separate systems, but if the only feasible 2 plate mode is spillover, so be it

The spare CU100 x BD50 is simply that and no holding plates, lines, or controller. While I am not keen to spend yet more money, if I need 3 plates then it would be nice to buy an expansion valve plate that will work with my spare CU100

The key seems to be what compressor is used on the CU100 reefer units, and was it the same unit over time
Dometic specs are of no help at all
Google suggests that the newer units are BD50, but this should be confirmed.
My spare CU100 is a Dometic 2015 model so hopefully the BD50.
The in service units age are unknown - how to tell if a BD35 or BD50 compressor?

Holding plates are Adler Barbour Power Plates. 450mm wide x 280mm high.
The 450 side is sitting horizontally, and connections are on the 450mm side, top R corner
I need to rotate the freezer plate(s) 90 degrees so that the 450mm dimension is now vertical to fit the new freezer side of the box. Connections therefore will be top R, but vertical input as opposed to the designed horizontal input.

I have:
5.5 KVA genset
120A alternator with smart regulator on the engine
6 x 6V trojan golf cart house batteries. (RE-105)
Solar that puts out 20A in the blazing sun.
Charger is 140A, throttled down to 15% of the Trojan acceptance rate.

While the current system must support the new fridge project, the mods never end, and upgraded solar is next with lithium batteries when the Trojans die.

Boat is a Tayana Flying Dutchman 50

I intend to insulate the box as much as possible using EPS, AB or a combination of both, depending on how the construction goes next week and how difficult to obtain what I need to do it right locally.

Thanks to all for the help, and I am getting there.......

To find out if it is a BD35 or BD50 . look at the sticker on the front of the compressor , it should say .

Dometic support is virtually none existent .

Also , there is a lot more to designing a TXV based system then just putting on the valve. I recommend buying a plate with the appropriate line set and couplers that will connect to your compressor. Avoid the Power Plates , just get an aluminum evaporator plate will serve you best.

Regards John.

[john61ct]

Seems to me the solution is 2x BD50 feeding the freezer (maybe convert to TXV?), and spillover to a fridge section, leaving a spare compressor.

_____
On the evaporator vs holding plate issue.

Some claim the latter are inherently more energy efficient, but it seems they basically just replace battery capacity to store coolth energy.

No question they take up valuable space internal to the box, weigh a lot, and are a lot more expensive - although that goes away when you already own them.

So other than those who sell them, the consensus seems to be they are only worthwhile if you will have significant and frequent "free, excess" electric production that would otherwise be wasted.

It does seem that going to an LFP bank would tilt the odds in favor of a holding plate design, since they will charge much more quickly, and are so much more expensive per usable AH.