Johnson Controls YORK YVAM 0350, Руководство по эксплуатации и техническому обслуживанию

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System operating procedures
The following section provides information on pre-starting, start-up, and operation of the chiller.
Pre-starting
Before starting the chiller, make sure that the display shows the message SYSTEM READY TO
START . The panel can only boot up when line power is available to the variable speed drive
transformers and the UPS battery in the power panel is present and connected with the battery
disconnect switch closed.
CAUTION
After periods of waterside maintenance or prolonged shutdown, vent any air from the chiller water
boxes before starting the water pumps. Failure to do so can result in pass baffle damage.
Start-up
If the chilled water pumps are manually operated, start the pump. The Control Center does not
allow the chiller to start unless chilled liquid flow is established through the unit. If the liquid pumps
are wired to the Microcomputer Control Center pump run contacts, the pump automatically starts,
and so this step is not necessary.
Note: The coolant temperature inside any Johnson Controls-supplied liquid-cooled motor
starter must be maintained above the dewpoint temperature in the equipment room
to prevent condensing water vapor inside the starter cabinet. Therefore, an additional
temperature-controlled throttle valve is needed in the flow path for the starter heat exchanger
to regulate cooling above the equipment room dewpoint for applications using cooling
sources other than evaporative air-exchange methods, such as wells, bodies of water,
and chilled water. The temperature control valve must be the type to open on increasing
drive coolant temperature, fail-closed, and set for a temperature above dewpoint. It can be
requested as factory-supplied on a chiller order by special quotation.
The Start/Stop control depends if the chiller Control Source is set to Local or to one of the Remote
types from the chiller Setup > Operations screen. Start is operated under the following conditions:
• Only the keypad when the chiller is set to local mode
• Remotely through digital inputs in digital or analog remote mode, but the local keypad start
must be pressed initially to enable the run permissive
• By the SC-EQUIP in BAS (ISN) remote mode, but the local keypad start must be pressed
initially to enable the run permissive
To start the chiller, press the Start button on the Home Screen on the display panel. In Local control
source, the chiller then starts. In remote ISN, analog, digital, or modem, a remote start command
must also be provided to the correct input connection.
When the control is changed to local mode from any other source, it will remain in Run if already
running or remain in Stop if already stopped. A hardware Safety Stop button is also located on the
side of the panel.
The chiller will start if the following conditions are met:
• Leaving Chilled Liquid Temperature is above the setpoint
• Chilled liquid flow is established
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