Johnson Controls YORK YMC2 Operation And Maintenance Manual

board called the SC-EQUIP provides Johnson Controls and YORK mechanical equipment such as the
YMC
2
chiller with BAS networking connectivity.
The chiller also maintains the standard digital remote capabilities as well. 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
160.84-PW1 and PW3):
• Remote start
• Remote stop
• Remote leaving chilled liquid temperature setpoint adjustment: BAS coms, analog signal, (0-10
VDC, 2-10 VDC, 0-20 mA or 4-20 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. Refer to the Field Connections section of the Wiring
Diagram (Form 160.84-PW2 and PW4) for further details. 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 those below:
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 the saturated condenser temperature is less than 35.0°F (1.6°C). This helps mitigate
condenser freeze due to plant issues in brine applications.
If the contacts are closed due to only the saturated condenser temperature, they are opened when
the saturated condenser temperature returns above 40.0°F (4.4°C). If the existing logic calls for
them to be closed, they remain closed.
Some screens, displayed values, programmable setpoints and manual controls exist for only
service technician use. They are only displayed when logged in at service access level or higher. The
setpoints and parameters displayed on these screens are explained in detail in YORK YMC
2
Service
Manual (Form 160.84-M2). These parameters affect chiller operation and should never be modified
by anyone other than a qualified service technician. The advanced diagnostics and troubleshooting
information for service technicians are included in YORK YMC
2
Service Manual (Form 160.84-M2). Also
included in the service manual are detailed descriptions of chiller features, such as capacity control,
refrigerant level control, variable speed drive (VSD), and magnetic bearing controller (MBC).
The chiller operating program resides in the OptiView
™
Control Center microboard. Software
versions (C.OPT.18.xx.yzz) are alphanumeric codes that represent the application, language
package and revision levels as below. Each time the controls portion or language section is revised,
the respective revision level increments.
• C: Commercial chiller
• OPT: OptiView
™
• 18: YMC
2
Mod B Chiller
YMC
2
Mod B with OptiView Control Center
16

Johnson Controls YORK YMC2 Specifications

General

Brand	Johnson Controls
Model	YORK YMC2
Category	Chiller
Language	English