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globalwave
09-09-2011, 01:15 PM
hi guys

this is my first thread, recently replaced a condensing unit CGP12TB3 ( Compressor GB12TB3, HMBP, 3/8HP) made by Cubigel (orignally ACC).

in order to get some cooling, had push refrigerant untill High Pressure reached to is 250 psi and low 20 psi (i read somewhere the maximum high pressure for R134a is 13.09 Bar about 189psi)

now i am getting +3c. Ambeint temp is 26c. refrigerant is R134a. its a Sadia double door commercial fridge.

My problem:

(1) I suspect cap is blocked but not sure.
(2) supplier suggeted Capillary size "BC3 BULLET RESCTRICTO" from Supco. (its single feed system) but according to Supco selection chart it seems not correct. please help.
Royal241
09-09-2011, 01:23 PM
observe how it equalizes, if too slow then there is a restriction most likely at the cap. recover *****, cut the cap tube at the drier, look for build up inside, it blockage present then cut about 6inches, should be much better (use a file to cut and break cap tube). replace drier.
simon@parker
09-09-2011, 01:28 PM
if yr capillary is blocked or restiting it will have a cold spot or frost forming this also happens w a unit short of gas discharge seems bit high is yr condenser clean if you have changed compressor did u change drier and give a nice gentle purge through with nitrogen also did you get a good vacume ? as air non condensables will give you hi head as well best of luck with that :)
globalwave
09-09-2011, 02:27 PM
Royal241

it takes few minutes before it equalizes, can i cut longer than 6" if required and compensate the removed length with new cap of same length. i would prefer to follow your suggestion instead of changing the full length of cap for obvious reason.
globalwave
09-09-2011, 02:35 PM
Compressor wasn't burnt, had mechanical fault, replaced the complete condensing unit as condensing coil was blocked with solid oil grease(restaurant Kicthen). there is no frost on cap itself.
Gary
09-09-2011, 07:20 PM
Royal241

it takes few minutes before it equalizes, can i cut longer than 6" if required and compensate the removed length with new cap of same length. i would prefer to follow your suggestion instead of changing the full length of cap for obvious reason.

A cap tube restriction is almost always at the inlet.

Unless the cap tube is very short, a few missing inches isn't going to make a noticeable difference.

Also keep in mind when you install the new drier that on a cap tube system the drier should be tilted downwards in the direction of flow.