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hsn157134
01-10-2014, 07:16 PM
Hi
I have an A/c unit with scroll copmpressor.
problem is: the liquid line specialy after sight glass is cold ( near of TXV is colder) and when compressor is started the amperage become High and variable.

i read an article that said if there is a restriction, the amperage must be low because of starved Evap and low suction pressure.

whats your idea?

nuwanchamara
01-10-2014, 07:19 PM
Replace filter drier

hsn157134
01-10-2014, 07:23 PM
i did but the problem is not solved

hsn157134
01-10-2014, 07:26 PM
unloaded compressor amperage is 13
loaded is between 30-50 !!!
seems there is a restriction such as oil in pipes
do you agree?

frank
01-10-2014, 07:30 PM
What is the compressor nameplate running amps?

If it is running way above the nameplate FLC then it sounds like your compressor is goosed. A blockage will not make the compressor draw that sort of amps.

hsn157134
01-10-2014, 07:36 PM
copeland scroll ( nominal 30 A )

so, you think Comp. is down.

frank
01-10-2014, 08:38 PM
Megger it to find out.

RANGER1
01-10-2014, 10:14 PM
Suction & discharge pressures at the same time would also be helpful.

hsn157134
02-10-2014, 09:45 AM
Discharge 225 psi
Suction 45 psi
Amperage between 35 - 50 ( copeland scroll / nominal 30 A)
Unloaded: 13 A
And the liquid line is cold specially after sight glass

Hamza Alg
02-10-2014, 06:16 PM
Was your indoor unit running as heat pump or cooling?
Have you checked compressor winding?
After sight glass should be warm subcooled liquid. If its cold that could be a sign short of refrigerant. If you refer to PH chart you will know the compressor will always pull too many amps when its under charged.

hsn157134
02-10-2014, 06:53 PM
its a cooling unit and the compressor winding is normal.
there was problem when the charge was complete.
plus, the sight glass indicator shows the system is wet.
after a vacume, the problem was too.
( sorry for bad English)

mikeref
03-10-2014, 09:09 AM
Measure the voltage going to the compressor when the compressor is loaded. Iranian supply should be 230 volts at 50 Hertz using single phase. (Source: Google search.)
Are you using R22? Have you tested the Capacitors?
The new filter/Drier will help sort the moisture problem but not the compressor.

mikeref
03-10-2014, 09:27 AM
Drawing 30 Amps on any single electrical item at 240 Volts/ 50 HZ is beyond Australian standards. Drawing 30 amps on one phase of a 3 phase compressor is common in industrial applications.

hsn157134
03-10-2014, 10:45 AM
Its a 30 tones A/C with r22
And I changed the drier but the problem is on.
So I take the comp and sent for Seller to check it
And I clean all of system.
But I like to know whats the reason of problem.

sterl
03-10-2014, 04:02 PM
What voltage system is this thing operating on?

(1) 30 Amp Scroll on a 30 Ton Chiller for (1) machine comes close to corresponding with a 460V 3 Ph 60 Hz arrangement....On 230 V 50 HZ the current should be a lot higher. What does the entire compressor nameplate read in terms of Voltages and Current?

hsn157134
03-10-2014, 05:15 PM
What voltage system is this thing operating on?

(1) 30 Amp Scroll on a 30 Ton Chiller for (1) machine comes close to corresponding with a 460V 3 Ph 60 Hz arrangement....On 230 V 50 HZ the current should be a lot higher. What does the entire compressor nameplate read in terms of Voltages and Current?

my mistake.
15 tone is true and nameplate is 380V/ nominal A: 30