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tempman
01-02-2006, 01:15 PM
I am stumped on this walk in cooler
Went to a service call for no cooling in cooler
found 2 leaks & repaired. Cooler not cooling down yet. Got some reading
R-22 Low @ 12# Hight @ 175# ambient temp 35 F
suction temp at compressor 28F
suction temp at evap coil 42F
Liquid line @ 70F
Discharge line @ 120F
any info appreciated

4x4freak
01-02-2006, 01:24 PM
Those pressures are too low. The suction should be running around 50. Do you have a fan cycle or headmaster on it?

pecmsg
01-02-2006, 01:27 PM
It was explained in your last post that you really should get more training.

http://www.hvac-talk.com/vbb/showthread.php?threadid=89834

tempman
01-02-2006, 01:43 PM
I just made the transistion from hvac to refrigeration about a year ago and i know i need more training and beleive me i am reading and going to every refrig class there is.
i have good understaning of the refrig cycle and most of the accesories.
I posted here so i can get help and any help is appreciated I am a fully licensed contractor not some DIY. I understand training is needed but working full time with a family i am trying my best to learn any info.

Yes this is an outdoor unit and it does have a headmaster
I am familair with this device as it does the job similar to a fan cyling switch but much effiecnt. i already tested the txv. and if the problem lies in the headmaster what is the best way to test it

pecmsg
01-02-2006, 01:57 PM
Location:MICHIGAN, Detroit
Occupation:MECHANICAL CONTRACTOR
Part Owner of hvac/r business
8 years experience in HVAC/R

I dont have a problem helping, but what your asking should have been learned in the 1st or 2nd year.

icemeister
01-02-2006, 02:00 PM
Originally posted by tempman
......suction temp at compressor 28F
suction temp at evap coil 42F
[/i]

That makes no sense to have a lower suction temperature at the compressor than at the evaporator outlet unless you have a TEV leaking through the equalizer line or an internal leak in a suction/liquid heat exchanger. If those numbers are correct, I suspect the former.

rayr
01-02-2006, 02:38 PM
Those temps sent up a red flag to me also....... Is there a sight glass on the system???? Is there a temp drop accross the LL Drier??? If the sight glass is full or slight bubbles, block off the condenser coil and get the head up to around 225-240 and see what happens. Get back with the numbers.

mark 11
01-02-2006, 03:08 PM
Restriction in suction line maybe???

tempman
01-02-2006, 03:40 PM
There is no temp drop across the LL drier and the sight glass is full when I go there tommorrow I will get the head up and see what happens. I will also take more temps at differnt location in the system. and thanks for the advise guys.

Freezeking2000
01-02-2006, 08:36 PM
PERHAPS THE SUCTION LINE IS COLD FROM BEING OUTSIDE?

jdservice
01-02-2006, 10:13 PM
You have pressures running W/I freezer temp. You should try getting the suction pressure up to W/I cooler design. Maybe 20 to 25 degrees. Sounds like a TXV problem or the evap.coil is iced up.

mtnwrench
01-03-2006, 02:50 PM
those numbers are jacked, suction should be around 50 for walk-in, numbers you are giving are for freezer. Get the head up around 225 and repost numbers. You stated you checked the txv, how did you do this? Looks to me like the evap superheat is sky high. Dump some hot water on the txv and see what the numbers are again after five minutes. Sounds like a txv problem to me.

sddragon
01-03-2006, 11:40 PM
We also produce walk in cooler (see link below). I think you have to check whether there's leakage in the copper pipe.

[Edited by Lusker on 01-04-2006 at 10:22 AM]

cold in alberta
01-08-2006, 10:05 PM
not uncommon to have a 180 psig headmaster on r-22 so 175 psig is not out of reason on the high side (about 95 cond.).however your low side temps and pressures worry me.was the cooler completely out of gas or just low and was their frost on your txv equalize line-a sure sign the txv is screwed-please give more info and you will get better help.