High condenser sub cooling

[tvrao]

Hi,
I have a problem with the condenser running for 134system dryer unit. It was punctured beyond repairs due to unknown problem. so I have installed a non standard condenser unit meant for r22 as i do not have a similar one. It was placed away from the original position and on ground level (original condenser was at 3feet height).
On starting the unit, we find compressor was running with high pressure and sub cooling is also very high about 25-30k. what could be the reason for this High pressure?

will the distance and reduction in height affect the Hp? If i can bring down the hp i can solve the other problems.
134a system

hp-225psi
condensing temp- 24c
inlet air temp-23-24c
outlet air - 29-30

[monkey spanners]

Is the condenser piped correctly?

[The Viking]

Over charged????


:cool:

[Brian_UK]

Is the new condensing unit the correct size?

[tvrao]

Condenser is not overcharged for sure. infact charge is inadequate.
Condenser is not originally designed for air dryer application. It was designed for R22 air handling system and constructionally is different in shape . its capacity size is more or less same and pipe size looks to be same.

[mad fridgie]

You have air in the system.
Remove refrigerant , vacuum to 500micron or below, recharge with new refrigerant.

[tvrao]

i would like to know whether any modification is required. i mean
1. its increased distance from compressor will create any resistance?
2. original condenser was placed at a height above the liquid accumulator. now the present condenser piping is below the accumulator level. will this lift in piping create more resistance for flow and cause pressure to increase?

[Brian_UK]

i would like to know whether any modification is required. i mean
1. its increased distance from compressor will create any resistance?
2. original condenser was placed at a height above the liquid accumulator. now the present condenser piping is below the accumulator level. will this lift in piping create more resistance for flow and cause pressure to increase?You are clutching at straws here, this is not your problem.

[passandscore]

You have air in the system.
Remove refrigerant , vacuum to 500micron or below, recharge with new refrigerant.


I agree with Mad Fridgie. Sounds like non-condensables!

[nike123]

Check system for non- condensible gases by stooping it, isolate compressor, turn on condenser fan and after 10 minutes of fan working, measure air entering temperature and pressure in condenser. If you have any difference from PT chart for used refrigerant you have non-condensibile gases.

After that check is done, and you find that non condensible gases are not problem here, then you probably have situation where liquid is backing up in condenser. It could be because of liquid receiver placement, but not necessary because of that. Any restriction in line from condenser to TXV can be possible reason and therefore you need to check everything by accurate temperature measurement of liquid pipes before and after each component on that line.

[tvrao]

Hi everyone. Thanks and Let me share my experience with this problem which is sorted out now. As many of you have expected, I found the air in the refrigerant system. The evaporator coil was leaking inside and entered into the LP side of the circuit. It has resulted continues increase in HP and unit was tripping.

Regards