Johnson Controls YORK Tempo YLAA Series, Installation Operation & Maintenance

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FORM 150.72-NM1 (1020)
21
JOHNSON CONTROLS
2
Unit On/Off
The microprocessor control center is capable of
displaying the following:
• Return and leaving liquid temperature
• Low leaving liquid temperature cutout setting
• Low ambient temperature cutout setting
• Outdoor air temperature
• English or Metric data
• Suction pressure cutout setting
• Each system suction pressure
• Discharge pressure (optional)
• Liquid Temperature Reset via a Johnson Controls
ISN DDC or Building Automation System (by
others) via a 4 to 20 milliamp or 0 to10 VDC
input.
• Anti-recycle timer status for each system
• Anti-coincident system start timer condition
• Compressor run status
• No cooling load condition
• Day, date and time
• Daily start/stop times
• Holiday status
• Automatic or manual system lead/lag control
• Lead system definition
• Compressor starts and operating hours
(each compressor)
• Status of hot gas valves, evaporator heater
and fan operation
• Run permissive status
• Number of compressors running
• Liquid solenoid valve status
• Load and unload timer status
• Water pump status
Provisions are included for: pumpdown at shutdown;
optional remote chilled water temperature reset and two
steps of demand load limiting from an external building
automation system. Unit alarm contacts are standard.
* Intensity of Protection European Standard
** International Electrotechnical Commission
The operating program is stored in non-volatile memory
battery backed RAM to eliminate chiller failure due to
AC powered failure/battery discharge. Programmed
setpoints are retained in lithium battery-backed RTC
memory for 5 years minimum.
COMMUNICATIONS
• Native communication capability for BACnet
(MS/TP) and Modbus
• Optional communication available for N2 and
LON via eLink option
HIGH AMBIENT KIT
Allows units to operate when the ambient temperature
is above 115°F (46°C). Includes sun shield panels and
discharge pressure transducers.
BUILDING AUTOMATION SYSTEM
INTERFACE
The Microprocessor Board can accept a 4 to 20 milliamp,
0 to10VDC input to reset the leaving chiller liquid
temperature from a Building Automation System.
• The standard unit capabilities include remote
start-stop, remote water temperature reset via a
PWM 4 to 20 milliamp or 0 to 10VDC input sig-
nal or up to two stages of demand (load) limiting
depending on model.
• The standard control panel can be directly con-
nected to a Johnson Controls Building Automated
System.
POWER PANEL
Each panel contains:
• Compressor power terminals
• Compressor motor starting contactors per
l.E.C.**
• Control power terminals to accept incoming for
115-1-60 control power
• Fan contactors and overload current protection
The power wiring is routed through liquid-tight conduit
to the compressors and fans.