YORK YMC2 — CONDENSER - FLOW SWITCH OPEN

The panel shows the message as CONDENSER - FLOW SWITCH OPEN. The manuals print it only in this form; there are no other variants or abbreviations for this model.

The chiller has lost its condenser liquid flow signal: the condenser water flow switch is open at a moment when the controls expect condenser water to be moving. The fault table words it as a Loss of condenser liquid flow signal while running.

This is a cycling fault, not a lockout: it stops the machine, and the chiller comes back by itself once the condition clears. A software change notice for this model adds one classification detail — in the software version it covers, this fault was changed from a Standard Soft Shutdown fault to a Fast Soft Shutdown.

• The condenser water flow switch has remained open for 5 continuous seconds while the chiller was running or in soft shutdown.
• One manual extends the same 5-second condition to the period at least 45 seconds after MBC startup is initiated, so a switch still open at that point also sets the fault.
• One manual notes that this check is bypassed until System Run is achieved, so the fault cannot be raised earlier in the start sequence.

• 5 continuous seconds — how long the condenser water flow switch must stay open before the fault is set.
• 45 seconds — per one manual, the check applies at least 45 seconds after MBC startup is initiated.

No manual reset is described. The fault releases on its own and the unit comes back without operator action: The chiller will automatically restart when the flow switch closes. One manual adds that the fault will clear instead if the chiller run command is ceased. The software change notice states the release conditions the same way: the fault is released when the condenser flow switch closes, or when the Run Permissive is False and the Chiller State is Stopped.