9
High Refrigerant Pressure
If the compressor discharge refrigerant pressure exceeds the setting on the high refrigerant pressure safety, the
compressor and pump will shut off and the High Refrigerant Pressure LED will be illuminated. Pressing the Alarm Reset
button will reset the High Refrigerant Pressure fault, as long as the High Refrigerant Pressure switch located at the
discharge of the compressor has been manually reset.
Low Refrigerant Pressure
If the compressor suction pressure drops below the setting on the low refrigerant pressure safety, the compressor will shut
off, the pump will remain running, and the Low Refrigerant Pressure LED will be illuminated. Pressing the Alarm Reset
button will reset the Low Refrigerant Pressure fault, as long as the refrigerant pressure has risen back up above the safety's
cutout level.
Freezestat
(EQ2 series only) If the coolant temperature being delivered to the process drops below the setting on the Freezestat, the
compressor will shut off, the pump will remain running, and the Freezestat LED will be illuminated. The Freezestat should
be set 10°F (5°C) above the freezing point of the glycol solution and 10°F (5°C) below the minimum operating temperature.
The Freezestat is factory set at 38°F (3°C). In order to reset the Freezestat fault press the Alarm Reset button on front
control interface.
Low Oil Pressure
This LED is nonfunctional on standard units and will be activated only if the unit has been modified to include a low oil
pressure sensor (typical for semi-hermetic reciprocating compressor units). If the unit has a low oil pressure sensor and the
oil pressure in the compressor crankcase drops below the factory set level on the oil pressure switch, the compressor and
pump will shut off, and the Low Oil Pressure LED will be illuminated. In order to reset the Low Oil Pressure fault, press the
Alarm Reset button after resetting the mechanical pressure switch located inside of the cabinet near the compressor.
Over Set Point
The Over Set Point LED will be illuminated if the To Process temperature exceeds the Set Point temperature by more than
5°F (3°C). This fault causes only an alarm indication (horn and/or remote contact) and the chiller will continue to operate.
Although the Over Set Point LED will turn on immediately whenever the temperature is out of range, the alarm relay is
disabled for 30 minutes after start-up or after a change in set point. The alarm will automatically clear when the To Process
temperature is no more that 5°F (3°C) above the Set Point temperature.
Under Set Point
The Under Set Point LED will be illuminated if the To Process temperature drops below the Set Point temperature by more
than 10°F (5°C). This fault will shut off the compressor, but the pump will continue to run. Although the Under Set Point
LED will turn on immediately whenever the temperature is out of range, the alarm relay is disabled for 30 minutes after
start-up or after a change in set point. Pressing the Alarm Reset button will reset this fault.
Pump On
The Pump On LED will be illuminated whenever the pump is running. If the pump is shut off due to a safety, the Pump On
LED will turn off. The Start button must be pressed in order to restart the pump.
Compressor On
The Compressor On LED will be illuminated whenever the compressor is running. The Compressor On LED will cycle on and
off with the compressor. The compressor will not come on unless the pump is already running and the To Process
temperature is above the Set Point temperature.
