Pump down without receiver?

[mcairrepair]

I'm working on the walk-in cooler in a MAC 6 fo one of our mcdonald's store. Evaporator is a Bohn model MCA0901D. It's got a starved evaporator, uneven frost pattern. I need to know what type of refrigerant is in this thing, but there's no labels and I don't see a receiver where I can pump the refrigerant into and take a PT reading. Any ideas on how to find out what's in this thing? Originally it's supposed to be R22. I know the walk-in freezer has 404a, but I don't know about the cooler. I'm sorry I don't have the operating pressures on me right now.

[nchvac]

Can you isolate a part of the system with pressure ports (indoors or outdoors where both liquid and gas state are present)and take a pressure reading and compare it to a saturation chart? That should tell you what is in there shouldn't it?

[rayr]

Check the expansion valve, check the compressor for what it is supposed to be for and the oil it has in it. Go from there. Dump the charge and start over.

[crackertech]

Check the expansion valve, check the compressor for what it is supposed to be for and the oil it has in it. Go from there. Dump the charge and start over.

You meant to say reclaim the charge no one dumps it any more.:D:D:whistle:

[pecmsg]

You meant to say reclaim the charge no one dumps it any more.:D:D:whistle:

And you believe in the

Easter Bunny……

Santa ………..

Love at first sight………

Right!

[icemeister]

And you believe in the

Easter Bunny……

Santa ………..

Love at first sight………

Right!

He doesn't like Santa.

CT's still PO'd 'cuz he didn't get what he asked Santa for 30 years ago:

http://i92.photobucket.com/albums/l1/icemeister/rockem_sockem_robots.jpg

:D

[RuudInstaller]

If this unit is in a galvanized metal enclosure it is very likely that the freezer was 502 and the cooler is 22. However anything is possible. All of the old ones that we work on for McD's are running 408 in the freezer and 22 in the cooler. The newer mac units that are tan are running 404 for freezer and cooler. Check the TXV in the evap for refrigerant type but I bet it is still running on 22. By the way the receiver is mounted underneath the unit, you can't see them. You can access the king valves on both receivers on the left side of the unit just before the flare filter driers. Good luck.

[crackertech]

And you believe in the

Easter Bunny……

Santa ………..

Love at first sight………

Right!

Why yes I do.:D

You forgot the great pumpkin.:LOL:

[crackertech]

He doesn't like Santa.

CT's still PO'd 'cuz he didn't get what he asked Santa for 30 years ago:

http://i92.photobucket.com/albums/l1/icemeister/rockem_sockem_robots.jpg

:D
Sniff......sniff......sniff.:gah::gah:why Santa why sniff....

[VTP99]

TOOTH FAIRY :grin2:

[cjpwalker]

You meant to say reclaim the charge no one dumps it any more.:D:D:whistle:

Absolutely - Always reclaim that cloud into your EPA certified recovery rag!

[rayr]

You meant to say reclaim the charge no one dumps it any more.:D:D:whistle:

LOL. Of course, dump it into a Recovery Cylinder. We don't Reclaim.To large a process and way to expensive for our needs:LOL:

[jaweberiii]

Dump the charge and start over.

I have to agree with rayr on this one!!! Dump it and pull one hell of a vacuum on it and start over.....be sure to mark it somewhere for the next tech:)

[ryan1088]

Any of the rest of you guys' paint the head of the compressor to match the refrigerant? One of our old school guys got me started on it and we have every one painted to tell you what refer is in it.

[jaweberiii]

Any of the rest of you guys' paint the head of the compressor to match the refrigerant? One of our old school guys got me started on it and we have every one painted to tell you what refer is in it.

hey ryan that's a good idea never thought of that!!!:oops::oops: