Alright guys, Ive been doing Commercial and Residential AC for five years but Ive just recently began doing service on refrigeration.(6-9 months)
Went to this True "sandwich prep" station last Friday night.
Model #Tssu4818m / Serial#Ae444oy / 134A
Found the "tap valve" leaking,recovered,changed tap valve,vacuumed and weighed in charge.
(I also changed the dryer to one with a high side service port.)
Data plate called for 11oz.(134A)
Upon start up pressures were about 12/120.(seemed low)
Condensor fan wasnt blowing much heat.(same as when I arrived)
Temp slowly came down to the 40`s from the 70`s.(fieldpiece bead in door)
Customer wanted to go home(11:00 pm),it was in the forties in the box so I told him to call if there was an issue the next day.
This morning he calls and tells me it cooled fine Saturday but Sunday it was in the fifties again.
I go out tonight recover,vacuum and weigh in charge again.
This is a cap tube system.
Pressures were 12/115.
Liquid line temp was 79.
Suction line temp was 68.
Once again no heat from condensor fan.
Due to the low Head pressure I began to add additional 134A.
Condensor was getting warmer,suction line temp dropped to 49 degrees.
Temp in box got into the mid 30`s.
So my question is could the the Data Plate have been wrong?
Does that happen often.
Or is there something Im missing?
I still couldnt get much heat from the condensor fan but I didnt want to overcharge it.
Finall pressures 18/140.
Suction line temp 49,liquid line 79.
What else should have I looked for?
Any suggestions will be applied and I will let you know the results.