YCAL chiller

[basshound71]

Have a YCAL chiller that just took over, we are having a problem with it shutting down on low suction pressure in low ambient conditions. Have unit set up for low ambient operation and have condenser vfd setup as it says in the book that I have. I don't have very much info on chiller so if somebody has some I would love a copy to my email. Going tomarrow to check out. Another tech was there today that doesn't have much chiller experience but got it running. Going to check transducers and such. Any help would be appreciated.

[milkyway]

Have a YCAL chiller that just took over, we are having a problem with it shutting down on low suction pressure in low ambient conditions. Have unit set up for low ambient operation and have condenser vfd setup as it says in the book that I have. I don't have very much info on chiller so if somebody has some I would love a copy to my email. Going tomarrow to check out. Another tech was there today that doesn't have much chiller experience but got it running. Going to check transducers and such. Any help would be appreciated.

DOES THIS HELP??

[ChillTek NC]

Verify your fan control on pressure and the differential, all your transducer's like you said will help for the head pressure controls your second stage fan in a 2 condenser fan config. Fan that is on vsd should be 1st stage fan, that is on whenever a compressor circuit is running. Also check your setting and operation of your hot gas bypass if you have one.

[basshound71]

Thanks chilltek, I know this is a prob with these chillers that run low ambient. Was set up completely wrong when picked it up. What should vfd be set on.

[ChillTek NC]

Here is something for you, that should be of good help. Its for YCAL0041-0065 Mod "D" ycal chillers, low ambient fan control config. Hope that helps...

[basshound71]

Thanks for the help guys, I also got with my ex boss at JCI and he told me that they have had probs with these. He recommended raising the cond fan on pressure above 400 (book says 385) with a diff pressure of 80 (book says 125). My chiller is a YCAL0019, the larger chillers like the 0033 says 425 with diff of 125. I don't understand why the difference in the two unless on the larger ones had a prob with oil return. What I did was split the difference, I raised cut i pressure to 400 with 100 differential and we will see what happens. What is happening is that the machine starts up there is such a pressure swing, the discharge pressure is driving the suction down and causing it to trip. It does automaticly lower suction setpoint at startup and slowly raise over the next couple of minutes until it gets to reg setpoint so it must also be doing it after running awhile. The cond. fans just can't get shut off fast enough when it's cold. I think it will be ok now though. JCI started the chiller up and had alot of things not set up properly so it has been a process. Luckily our customer is ok with that. Thanks again for the info guys.