Component Operation and Maintenance
Control Transformer and Fuses
The control system is divided into four separate circuits. The control voltage circuits are individually protected by fuses located on the transformer/fuse board. If any of the fuses are blown, first eliminate shorts, then use spare fuses supplied with unit. Use only type and size of fuse specified for your unit.
The small isolation transformer on the board supplies 24 volts to the main control board. The trans- former is internally protected. If the internal protector opens, the transformer/fuse board must be replaced. Also check the control voltage fuse on the main control board before replacing the trans- former/fuse board.
Fan Safety Switch
The Fan Safety Switch is located in the low voltage compartment and consists of a diaphragm switch and interconnecting tubing to the blower scroll. The Fan Safety switch is wired directly to the control circuit to activate the alarm system if the airflow is interrupted
High-Temp Sensor
The optional
Smoke Detector
The optional smoke detector power supply is located on the base of the upflow units, and at the top of downflow units. It is constantly sampling return air through a tube. No adjustments are required.
Water Detection Sensor
! WARNING
Risk of fire or explosion. Can cause injury or death.
Do not use near flammable liquids or for flammable liquid detection.
The optional water detection devices available are a point leak detection sensor and a zone leak detec- tion kit.
Figure 21 Liebert leak detection units
Liebert
Leak Detection Sensor
LT460 Zone Leak Detection Kit
The point leak detection sensor provides leak detection at a critical point. A simple
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