Anyone ever have a problem with the chilled water setpoint pot on a ucp1 going screwy and drifting off setpoint? I have one under contract that seems to be doing it, but I haven't caught it yet. The plant operator says he has seen the setpoint up as high as 60 when scrolling through the menu and then by just touching the knob, it drops right back to 45 and the chiller starts. Never any diagnostic, it's just the ucp1 "seeing" no cooling required and off cycling. Also one time, it apparently crashed when he switched from hold to auto on the vane control. Don't know if that's related, it may have been coincidental that the setpoint happened to drift passed the diff to stop setpoint at that moment. When I look at it, it will never do it. I can raise and lower setpoint and the display shows it being exactly where it should be for the knob position. I'm thinking just some contact cleaner might help it out. Any thoughts? When this starts to happen, is it just a matter of time before having to replace the 1U3 mod?
I've had to replace them when they fail internally before, just never seen this type of failure.