Used freezer holding plates

[john61ct]

Looking to source these cheap for some DIY 12V freezer experimenting.

Ideally in at least pairs, since I want to try some A/B testing on different configurations.

Shape / capacity not important, will be building custom boxen anyway.

[a64pilot]

If you can’t come up with any, you should be able to make some using automatic transmission coolers and SS cooking pans, the kind you see holding food in buffet tables, you could even just bolt the two together with a good sealant between them of course.

[john61ct]

Interesting, but a bit more deep into the DIY than I'd prefer.

And I think would make the results less applicable to what gets actually installed IRL.

When people replace their old-school boxes with more modern setups, I figure the old eutectic plates must end up somewhere. . .

[a64pilot]

Actually, I’d bet that is very close to what a Cool Blue cold plate is.
It sure looks like the correct size, and the auto trans cooler ought to be a very effective heat exchanger.
Get a big one if you go this route, one that pretty much fills the pan, copper lines with aluminum fins.

[Davidhoy]

I have 4 eutectic holding plates from my old boat. They were recently refurbished with new fittings and fluid, in preparation for a refrigeration upgrade that never happened as my boat was crushed by a 100ft motoryacht. I also have two brand-new Cool Blue compressors. If you're interested, we can chat...

-David

[Baba Buoy]

I just removed 12" x 16" freezer/refer cold plate. I also have compressor, engine drive belt driven compressor, freon filters and heat exchanger. All for cheap but no shipping.

[Richard Kollmann]

Originally Posted by john61ct

Looking to source these cheap for some DIY 12V freezer experimenting.

Ideally in at least pairs, since I want to try some A/B testing on different configurations.

Shape / capacity not important, will be building custom boxen anyway.

When selecting a holding plate evaporator the refrigerant coil inside must be of a tube size that maintains refrigerant flow velocity equal to output flow of compressor. The compressor's return gas line fitting size generally determines the evaporator coil diameter inside these plates. The colder you operate the plate the lower the refrigerant velocity will be. Too large of a refrigerant evaporator tube will trap oil. If the 12 volt compressor is to be a Danfoss BD model the evaporator coil should be ¼ inch OD tubing. Most of the surplus eutectic plates available have ½ inch OD tubing.

[john61ct]

Thanks Richard.

What 12V compressors would work with ½" tubing?

Or would I need to go to higher voltage?

Trying to avoid direct engine driven I think.

[john61ct]

Originally Posted by Baba Buoy

I just removed 12" x 16" freezer/refer cold plate. I also have compressor, engine drive belt driven compressor, freon filters and heat exchanger. All for cheap but no shipping.

Do you mean I would need to arrange a freight pickup?

Where is it located?

[john61ct]

Originally Posted by Davidhoy

my boat was crushed by a 100ft motoryacht.

Wow, my condolences!

Are those parts designed to work together?

I suspect you will want more than I could afford, maybe in the spring.

But yes, we can always PM, feel free!

[john61ct]

Originally Posted by a64pilot

It sure looks like the correct size, and the auto trans cooler ought to be a very effective heat exchanger. Get a big one if you go this route, one that pretty much fills the pan, copper lines with aluminum fins.

Well that certainly sounds interesting, maybe as I dive down that rabbit hole I'll get inspired.

Thanks

[OzePete]

Originally Posted by john61ct

Thanks Richard.

What 12V compressors would work with ½" tubing?

Or would I need to go to higher voltage?

Trying to avoid direct engine driven I think.

None! As previously stated, oil would be *retained in the evaporator coil thus starving and eventually destroying the compressor. This is especially so, if operating as a freezer like the OP intends. (*Some compressor oil is always travelling around the system with the refrigerant gas.)

In the unlikely event that the 1/2" evaporator tubing was fed at the top, cascading downwards and if a 1/4" 'riser' and suction line could be used, you may get away with using 1/2", but why risk it!
As stated, use 1/4" evaporator tubing for the low powered Secop BD35 (2cc) and BD50 (2.5cc) compressors. Or 3/8" tubing for BD80 (3.0cc) and Ozefridge BE90 (3.5cc) but with a 1/4" standpipe and suction line.

Use a 1/4" suction line regardless and never create 'oil traps' like running suction line up and over a door way!!! (Don't laugh, it happens!)

The issue is not 'voltage' it is velocity of refrigerant flow so that a correct oil level is retained in the compressor. . This is why systems need to be correctly engineered especially for component compatibility, if longevity is required!

Cheers, OzePete

[Richard Kollmann]

Originally Posted by john61ct

Thanks Richard.

What 12V compressors would work with ½" tubing?

Or would I need to go to higher voltage?

Trying to avoid direct engine driven I think.

Only SeaFrost and Grunert still sell 12 volt compressor/condensing units large enough to support evaporators with 1/2 inch OD tubing. The less expensive alternative would be 110/220 volt condensing units.

One company did sell for a short time icebox conversion kits with BD80 compressors and 1/2 inch OD evaporator holding plates. I know of three compressor failures in the first year. The hermetically sealed BD80 compressors are limited only to Low Back Pressures (LBP) applications this is why the low pressure evaporator tubing size is the same small size as required by the BD35 and BD50 compressors.

[john61ct]

Well alrighty then, getting you two to agree gets us all a gold star for today!

So I am now looking for secondhand eutectic holding plates at low pricing, any size but in pairs at least, and **must have** 1/4" evaporator tubing inside.

[john61ct]

What do y'all have to say about Glacier Bay cold plates?

Dunno yet about tube OD