Johnson Controls YORK YVAM 0350, Operation & Maintenance Manual

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Stopping the system
About this task:
To stop the chiller, complete the following steps:
1. Press the soft Stop button on the Home screen of the OptiView panel if in Local control or
send a stop command through the remote system if in Remote or BAS control. If the chiller is
in a remote-control source and the local soft Stop button is used to stop the chiller, the Start
button must be pressed before the chiller will again permit starts through the remote source.
In the event of an unusual circumstance requiring immediate stoppage, a safety stop switch
is located on the side of the control panel. Normal stop eases the driveline to stop and must
always be used instead of the safety stop during regular operation.
2. Stop the chilled water or condenser water pumps if they are not wired into the
Microcomputer Control Center, in which case it will shut off automatically. The actual water
pump contact timing operation is dependent upon the selection on the SETUP screen.
3. Open the switch to the cooling tower fan motors, if used.
Result
The OptiView Control Center can be programmed to start and stop automatically for a maximum
of once each day whenever required. See Schedule screen in OptiView control center functions and
navigation .
Safety stop
When depressed, the chiller will not run under any condition. For safety reasons, this position is
required for many maintenance tasks to be completed. The safety stop button must be rotated
clockwise to release the stop condition. The safety stop is not intended for normal shutdown of
the chiller. If it is used, an immediate stop occurs, which bypasses the programmed controlled
shutdown.
Operating logs
A permanent daily record of system operating conditions (temperatures and pressures) recorded at
regular intervals throughout each 24-hour operating period must be kept. Automatic data logging
is possible by connecting the optional printer and programming the Data Logging function. An
optional status printer is available for this purpose. Figure 10 shows an example log sheet used by
Johnson Controls Personnel for recording test data on chiller systems. Log sheets are available in
pads of 50 sheets and can be obtained through the nearest Johnson Controls office.
Figure 10: Chiller log sheets
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