Johnson Controls YORK YVAM 0350, Operation & Maintenance Manual

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The graphic display also allows numerical information to be represented in both English
(temperatures in °F and pressures in psig) and Metric (temperatures in °C and pressures in kPa)
mode. It can also display many languages.
The control center continually monitors the system operation and records the cause of any
shutdowns (Safety, Cycling, or Normal). This information is recorded in memory and is preserved
even through a power failure condition. The user can recall it for viewing at any time. During
operation, the user is continually advised of the operating conditions by various status and warning
messages. In addition, it can be configured to notify the user of certain conditions using alarms. A
complete listing of shutdown, status, and warning messages is provided in Display messages .
The control center includes capabilities for remote control and communications. Common
networking protocol through the Building Automation System (BAS) allows increased remote
control of the chiller, including 24-hour performance monitoring by a remote site. An optional
circuit board called the SC-EQUIP provides Johnson Controls and YORK mechanical equipment such
as the YVAM chiller with BAS networking connectivity.
The chiller also maintains the standard digital remote capabilities. Both of these remote control
capabilities allow for the following standard Energy Management System (EMS) interfaces. The
actual connection details are in the Field Connections section of the Wiring Diagram ( Form 160.88-
PW1 and 160.88-PW3 ):
• Remote start
• Remote stop
• Remote Leaving Chilled Liquid Temperature setpoint adjustment: BAS coms, Analog signal,
(0 VDC to 10 VDC, 2 VDC to 10 VDC, 0 mA to 20 mA, or 4 mA to 20 mA), or pulse width
modulation (PWM)
• Remote Current Limit setpoint adjustment: BAS coms, Analog signal, (0 VDC to 10 VDC, 2 VDC
to 10 VDC, 0 mA to 20 mA, or 4 mA to 20 mA), or pulse width modulation
• Remote ready to start contacts
• Safety shutdown contacts
• Cycling shutdown contacts
The OptiView panel can be used to control the customer chilled and condenser liquid flow. A set
of contacts exists to initiate flow for each shell. Details are in the Field Connections section of
the Wiring Diagram ( Form 160.88-PW2 and 160.88-PW4 ). The chilled water pump contacts close
immediately upon execution of a chiller start command. They open coincident with the receipt of a
stop command or a fault other than the following faults:
1. LEAVING CHILLED LIQUID - LOW TEMPERATURE cycling shutdown.
2.
MULTIUNIT CYCLING - CONTACTS OPEN
or
SYSTEM CYCLING - CONTACTS OPEN
(Only if
Chilled Liquid Pump Operation is set to Enhanced)
3.
LEAVING CHILLED LIQUID FLOW SWITCH OPEN
cycling shutdown
The condenser pump contacts close immediately upon execution of a chiller start command. They
open coincident with receipt of a chiller stop command or fault other than CONDENSER-FLOW
SWITCH OPEN cycling shutdown.
If the chiller is stopped and the condenser pump contacts are open (flow off), the contacts close
when saturated condenser temperature is less than 35.0°F (1.67°C). This helps mitigate condenser
freeze due to plant issues in brine applications.
If the contacts are closed only due to the saturated condenser temperature, they are opened when
saturated condenser temperature returns above 40.0°F (4.44°C). If the existing logic calls for them
to be closed, they remain closed.
YVAM Control Center 18