A l a r m s
If the red alarm LED is illuminated, an alarm is activated. The chiller has automatically pumped down because it has detected a serious problem that could damage your process or chiller. Note that the alarm must be acknowledged before the control will resume operation by pressing the “Infinity” button. 
Problem | Possible cause | Solution |
A2.hi (Alarm light illuminat- ed) – If the “To Process” temperature exceeds the process high temperature deviation setpoint, it shuts down the chiller. Default is set to 20°F {11.1°C}.
The
Load is too high for the chiller.
Process coolant is not flowing between the supply outlet and return inlet.
Dirty condenser coil.
Have a certified refrigeration technician replace the solenoid valve.
Remove some load from the process.
Check for plugged pipes, closed valves, or failed flow switch(es).
Clean condenser coil. See Maintenance section entitled, Cleaning the Air- cooled Condenser.
| Ambient temperature is above 95°F | Lower ambient temperature or move |
| {35°C}. | the chiller to a lower temperature envi- |
|
| ronment. |
| Warm process coolant. | Lower the temperature of the process |
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| coolant. |
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|
Er.in (Input error) | Failed RTD. | Replace the RTD. See Troubleshooting |
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| section entitled, Checking or Replacing |
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| the Temperature Sensor and Appendix F |
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| entitled, RTD Resistance Chart. |
Loose RTD connection to the control.
Check RTD connection to the controller. Resecure as necessary.
Reversed RTD input. | Check RTD wiring. |
A2.lo | – | (Alarm light illumi- Load is too low for the chiller. |
nated) | – | If the “To Process” |
temperature exceeds the process low temperature deviation setpoint, it closes the liquid line solenoid valve and the compressor pumps down and shuts down. Default is set to 4°F {2.2°C}.
The chiller’s compressor will automatically restart once the “To Process” temperature exceeds the
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