High Suction Pressure?

[te50]

Hi Guys, unfortunately I have been given the task of looking after a carrier 5H60 Compressor and associated air conditioning equipment. Problem I seem to have a much higher than normal suction pressure, low liquid temp and to me the compressor seems a little noisy. It is an exact copy of a unit standing next to it. the good unit has a high p of 200psi, suct of 33 psi. 80 psi oil pressure(about 50 true psi), discharge gas temp 86 deg f, liquid temp 120 f and suction gas temp of 22deg f. The not so good one, 205 high, 80 suction, 100 oilpressure(about 20 psi true), discharge gas 115 deg, liquid temp 55 degf and 70 deg suction gas temp.
Is this system over or under charged? It was working with simular readings till a few days ago when another operator connected another system to it and dragged out a lot of gas. He then recharged the system but now all the readings are different as is the performance.
Any advice much appreciated
Oh and it is water cooled refrigerant if that helps

[Gary]

Pressures are meaningless if we don't know what refrigerant is in the system.

[te50]

Sorry about that R22 is the refrigerant, thanks

[Gary]

Here is a list of the temps/pressures needed to troubleshoot a system:

Evap air/water in temp
Evap air/water out temp
Low side pressure or saturation temp
Suction line temp at evap outlet

Cond air/water in temp
Cond air/water out temp
High side pressure or saturation temp
Liquid line temp at receiver or condenser outlet

The more information provided the more accurate the diagnosis.

[D.D.KORANNE]

Check valves reeds ; could be leaking back . Measure current & compare it with the good one

[Sandro Baptista]

T50,

Check if there is air in the system. If the liquid temperature at outlet of the condenser is much lower (5 K for instance) than the corresponding pressure saturation temperature then you probably have it. Also check if the suction temperature superheated and compare with the saturated temperature, based on the pressure of the gauge. All this is related with the partial pressures of the refrigerant and air :) .


See if the compressor is working with full capacity (check solenoid's capacity).

Baptista

[anto]

check for compressor leak back