Liebert 50 & 60Hz, 8 Tons user manual Optional/Custom Alarms, Change Filter

Alarms

5.2Optional/Custom Alarms

5.2.1Change Filter

Periodically, the return air filters in the evaporator must be changed. The Change Filter alarm noti- fies the user that filter replacement is necessary. A differential air pressure switch closes when the pressure drop across the filters becomes excessive. The switch is adjustable using the procedure on the switch label.

5.2.2Firestat

The optional firestat feature is a bi-metal operated sensing device with a closed switch under normal conditions. Connected between pins 1-8 and 1-9, this device will shut down the entire unit.

5.2.3Smoke Detector

The smoke detector is located in the unit, the optional smoke detector power supply is located in the electric panel. It constantly samples return air through a tube. No adjustments are required.

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