On the display
The panel reads Condenser - Flow Switch Open. The manuals print the wording in two forms — “Condenser - Flow Switch Open” and “Condenser - Flow switch open” — for the same fault. It belongs to the cycling faults group, and cycling messages are recorded in the history log.
What it means
This is a cycling shutdown: the chiller stops running because the condenser flow switch has stayed open while the machine was running. The chiller automatically restarts once the flow switch closes. While the chiller is shutdown on this cycling shutdown, the condenser pump relay contacts (TB2-150/151) remain closed until the chiller is given a stop command or has another fault.
Why it appears
- The condenser flow switch has remained open continuously for the trip delay while the chiller was running.
- On heat recovery chillers, the heating condenser flow switch is monitored as well and can raise the same message.
Setpoints and thresholds
- One manual gives the trip delay as 5 s: the flow switch must remain open for 5 s continuously while the chiller is running.
- Another manual gives 30 continuous seconds, reduced to 2 continuous seconds with software version C.OPT.01.15A.xxx and earlier.
- In that manual, the check is bypassed for the first 30 seconds of “System Run”.
Reset and restart
No manual reset is described — the fault releases by itself. The chiller automatically restarts when the flow switch closes.
Because this is a cycling fault, the message is recorded in the history log, and the condenser pump relay contacts (TB2-150/151) stay closed through the shutdown until the chiller is given a stop command or has another fault.
Questions engineers ask
Why does my YORK YK show Condenser - Flow Switch Open?
The condenser flow switch has remained open continuously for the trip delay while the chiller was running. On heat recovery chillers, the heating condenser flow switch is monitored too and can raise the same message.
Does the chiller restart by itself after this shutdown?
Yes — it is a cycling shutdown, and the chiller automatically restarts when the flow switch closes. The event is recorded in the history log.
Do the condenser pump contacts stay closed during this shutdown?
Yes. The condenser pump relay contacts (TB2-150/151) remain closed while the chiller is shutdown on this fault, until the chiller is given a stop command or has another fault.
How long must the condenser flow switch be open before the chiller trips?
It depends on the software version: one manual gives 5 s continuously, another gives 30 continuous seconds, or 2 continuous seconds with software version C.OPT.01.15A.xxx and earlier. The check is bypassed for the first 30 seconds of “System Run”.
Messages next to this one
The same message on other models
Source
Written from the manufacturer's manuals for the YORK YK; every number and designation on this page is checked against them before publication. The row of the manual this message comes from:
All YORK YK messages: fault codes · YORK YK documentation · YORK manuals