York Liquid Chiller problems.

[kanodogg]

I have been working on a York Liquid Chiller M#YCAZ33BA3-46PA S#RKEM6953AA. I have a system fault of "Motor Current". I have (2) O6Z's reciprocating compressors 6 cylinder type. Both compressors are not original and have been replaced at one time or another. I went to the trouble shooting section of the operations manual and they suggest (3) different things will cause this alarm. Bad relay output board, bad motor protection device and faulty high pressure switch. The relay output board was replaced about a year ago. I checked my high pressure switch and is working correctly. I swapped out the motor protection between compressors and still had a system fault on Circuit (2) which disables Circuit 2 compressor. The tests I have done till now are as follows: Performed acid test on Circuit (2) compressor. Megged out the condenser fan motors. Both came back satisfactory. My next step is going to get oil sample to send over to a lab and get analyzed. Any other suggestions would be appreciated.

[nichpatch]

hi
check that there is not two hp switches on unit also check current relay which monitors compressor amps if it is reading too high or too low it will shut down unit hope this helps
nick

[Grizzly]

I have been working on a York Liquid Chiller M#YCAZ33BA3-46PA S#RKEM6953AA. I have a system fault of "Motor Current". I have (2) O6Z's reciprocating compressors 6 cylinder type. Both compressors are not original and have been replaced at one time or another. I went to the trouble shooting section of the operations manual and they suggest (3) different things will cause this alarm. Bad relay output board, bad motor protection device and faulty high pressure switch. The relay output board was replaced about a year ago. I checked my high pressure switch and is working correctly. I swapped out the motor protection between compressors and still had a system fault on Circuit (2) which disables Circuit 2 compressor. The tests I have done till now are as follows: Performed acid test on Circuit (2) compressor. Megged out the condenser fan motors. Both came back satisfactory. My next step is going to get oil sample to send over to a lab and get analyzed. Any other suggestions would be appreciated.

Hi can you please confirm that the model code you have posted is correct??
Cheers Grizzly

[kanodogg]

Yes,the model and serial number information is correct. This is a very old Chiller.

[johntheboy]

Try checking the motor thermistors. If they are open circuit then the compressor won't run. If the machine has an opto-isolator board then there should be 2 red LEDs in the top right hand corner that should be on if the thermistors are ok.