problems with york yaa c chiller

[paulwild]

:)hi can anyone help please been out to a york chiller it has 4 scroll comps working as 2 circuits 1and 2 useing common discharge and suction on each circuit, the prob is the unit is only useing a max of 2 comps at any time even if its not acheived temp the control display does not even show any run hours for comps 2 and 3 but in the service mode the system shows the all comps with 0 run time on 2 comps the unit has its eprom changed but no change would be gratefull of any input cheers guys

[al]

paul

you need the service password, check that the model is correct in the program and that the correct number of compressors is programmed. i havn't worked on one in ages so i can't remember the password and i could also be completely off the mark!!:rolleyes:

al

[paulwild]

hi al have checked all that mate all seems ok thanks for your reply

[neil74]

hi, l haven't worked on one of these for a while so it's a bit sketchy, l know this sounds stupid but are both circuits turned in in the options key?? you said it's had a new eprom if so you may need to re program the chiller and this may be why it says o run hours. l think you press program and then it's a combo of up and down keys pos up up down down up up. try a few examples until you get in oh and press enter. let me know if this helps. neil.

[DjP67]

What is the age of the chiller ?
Has the board got toggle switches for the compressors ?
are they switched on ?
Is the loading sequence correct (as in can it see the other compressos) ?