YORK YK — Warning - Condenser - Freeze threat from low pressure

The panel prints Warning - Condenser - Freeze threat from low pressure. The model's documents show the message with small capitalisation differences: Warning - Condenser - Freeze Threat From Low Pressure and Warning - Condenser - Freeze Threat from Low Pressure.

The control center warns of a possible freeze threat to the condenser or subcooler tubes while the chiller is stopped — the message itself names low pressure as the source of that threat. The warning messages table classes it as an auto-reset warning, meaning it clears on its own once a release condition becomes true.

• The Chiller State is Stopped while the Saturated Condenser Temperature has dropped under 34.0 °F — this pair sets the warning with or without the Drop Leg Temperature Sensor.
• When the Drop Leg Temperature Sensor is enabled, a Drop Leg Temperature under 35.0 °F is also required, so all three conditions hold at the same time.
• Without that sensor, the stopped state and the 34.0 °F condition alone are enough.
• The warning messages table words the set condition as three facts at once: no chiller operation, condenser saturation temperature under 34°F (1.1°C), and drop leg temperature under 35°F (1.7°C).
• The Subcooler Tube Freeze Prevention Logic gives the set threshold as 35.0 °F: the panel shows the message once the stopped chiller's Saturated Condenser Temperature drops under that value.

• Set — chiller Stopped with Saturated Condenser Temperature under 34.0 °F (both sensor configurations).
• Set — sensor enabled only: Drop Leg Temperature under 35.0 °F.
• Release — chiller no longer Stopped, or Saturated Condenser Temperature over 36.0 °F.
• Release — sensor enabled only: Drop Leg Temperature over 38.0 °F.
• Warning messages table figures: 34°F (1.1°C) and 35°F (1.7°C) to set; 36°F (2.2°C) and 38°F (3.3°C) to reset.
• Subcooler Tube Freeze Prevention Logic figures: 35.0 °F to set, 40.0 °F to reset.

The manual classes this as an auto-reset warning, so it releases by itself when any one of its release conditions becomes true: the Chiller State is no longer Stopped, the Saturated Condenser Temperature has risen over 36.0 °F, or — with the Drop Leg Temperature Sensor enabled — the Drop Leg Temperature has risen over 38.0 °F. The freeze-prevention logic puts the same behaviour in these words: This warning will automatically reset whenever the chiller is running or the Saturated Condenser Temperature is > 40.0 °F.