Anyone worked on a single compressor -150C ultralow

[paul_h]

I'm being sent to a revco ult7150-9-m15 freezer that has just one compressor, and refrigerant "1QRF0063"
Anyone know anything thing about the system and refrigerant? I'm guessing it's some blended refrigerant with huge glide to seperate them into different evaporators, but not sure how.
The compressor is a copeland scroll zr49k3-tfd-230 that looks stuffed

[paul_h]

No one?
Oh well.
Once more unto the breach, dear friends, once more... God for Harry! England and Saint George! And all that.

[Andy W]

I worked on some years and years ago, single compressor and cascade, models nowadays mean nothing to me now, the gasses were gasses that I have never come across since and would by now of been replaced by newer gasses, I would ring the manufacturers and ask for some information, I presume you have already searched on google. Sorry I cant help.

I do remember we had to manually add an additive in the oil when replacing the compressor.

[paul_h]

We do a bit of cascade -80 to -120, but I've never seen a single compressor system go so low in temp.

If it was easy, why isn't everyone doing it to save the costs of an extra compressor?
It sounds like an interesting system so I thought some old hands around here might know something about them.

My boss is getting the info and refrigerant from somewhere, I just thought I'd ask here while waiting for that info from him, just in case someone here had worked on one. Surely they (Revco) didn't just make the one freezer and ship it here?
Cheers.

[HallsEngineer]

Found your freezer, it says it uses an orbital rotary compressor single stage down to -150. http://www.thermo.com/com/cda/produc...123866,00.html

[paul_h]

Found your freezer, it says it uses an orbital rotary compressor single stage down to -150. http://www.thermo.com/com/cda/produc...123866,00.html

Yeah that's the one. The compressor is a fully marked copelend scroll, no problem there. But the "exclusive mixed refrigerant auto cascade" is what has got us beat, and is the interesting thing about this unit, and not available from any supplier in the country from what I'm told.

[dallan]

The auto-cascade is a series of distillation devices that separates the pre-blended refrigerant. You buy the refrigerant from Revco ready mixed and of the correct quantity, the down side is that everything will have to be shipped from the US.

Changing the compressor is relatively straight forward and there is a main liquid line drier. The worrying bit is that the refrigerant is extremely expensive so make sure it is leak tight or you have to buy another cylinder.

Usually what happens is a small leak develops on a rotalock which knocks the refrigerant balance off which overheats the compressor.

You can also buy a service manual from Revco for a couple of hundred dollars.

[The MG Pony]

The hobbiest field has been perfecting home brew auto cascades, best was -180 @ 250W so far.

[Bones74]

That refrigerant is a multiple blend. I beleive 5 or 7 refrigerants. And I believe about $1500.00 per charge. A leak will cause the refrigerant to seperate and it can't be topped off. Bummer. We do alot of auto cascade work. Make sure you put a sweeping agent in or you will have a major problem.

[Peter_1]

If you do a serach on a patent database, you will find a lot of these mixtures.
I service some Polycolds, same principle, autocascade.
The same way as they liquify LNG.

[Keitho-22]

I'm working on a revco -80c freezer, Stage 1 was out of gas so i put it on a pressure test and repaired leak. I evacuated the system and its ready to be charged with gas.

Theres 2 problems the display on the front is reading +199c
and I'm unsure what gas to charge with!

I've checked the technical data on the revco website and couldnt find what im looking for, Your help would be great

MODEL: ULT 2586-5-v12
SERIAL:U13D-169058-UD
ELECTRICAL: 220v - 12a - 50hz - 1ph
REFRIGERANT TYPE OZ
First 29700g24 15.25
Second 29702g04 5.9

[Grizzly]

I'm working on a revco -80c freezer, Stage 1 was out of gas so i put it on a pressure test and repaired leak. I evacuated the system and its ready to be charged with gas.

Theres 2 problems the display on the front is reading +199c
and I'm unsure what gas to charge with!

I've checked the technical data on the revco website and couldn't find what I'm looking for, Your help would be great

MODEL: ULT 2586-5-v12
SERIAL:U13D-169058-UD
ELECTRICAL: 220v - 12a - 50hz - 1ph
REFRIGERANT TYPE OZ
First 29700g24 15.25
Second 29702g04 5.9

Hi Kietho.
Following on from the link above supplied by Hallsengineer.
I registered on line and that allowed me into there manuals section.

Which has allowed access to the following manual.
INSTALLATION AND OPERATION
ULT 80 and ULT95.
Sadly ULT 2586 IS NOT LISTED.
But this manual may be of help.

I think it may be necessary to register first before the following are accessed.
Try it and see!

http://www.thermo.com/eThermo/CMA/PD...File_23514.pdf

OR
http://www.thermo.com/com/cda/resour...112136,00.html


once you have registered THE ABOVE GIVES ACCESS TO LOTS OF INFO.
CHEERS GRIZZLY

[zhoubo19810711]

I studied this auto-cascade refrigerating system in university 2 years before. And I think the most important for the system is the mixed refrigerant which is usually mixed by 3 to 7 pure refrigerants. The mixed refirgerant has very large temperature glid.
And the system was connected by several liquid-gas separators and heat exchangers(for heat recovery).

[Peter_1]

That refrigerant is a multiple blend. ....A leak will cause the refrigerant to seperate and it can't be topped off. Bummer. ....

Polycold is selling a special top-off mixture

[The MG Pony]

http://www.xtremesystems.org/forums/...d.php?t=144007

Learn a whole ton about autocascade here, infact you'll learn how to turn an ordinary Aircon into a -80c Cascade!

[Sturt]

I've seen a -80 cabinet charged with a single refrigerant from factory which involved the cylinder being agitated in a eunning chest freezer before being weighed into the system.

I would guess this applies to most single blends for low temp application so re-charging the system is going to be the biggest problem. as to what they all made up of...

Stuart.

[thebigcheese]

we do alot of low temp cabnets, the charge is critital and is something that u can learn over time dont be put off if it takes u a week to get the thing running correctly, have seen a few revco/ rebadged revcos go funny on temp readouts etc i would suggest switching of and cleaning the pcb??????????