Specifications
Table Of Contents
- Form 150.72-NM1 (908)
- GENERAL SAFETY GUIDELINES
- CHANGEABILITY OF THIS DOCUMENT
- TABLE OF CONTENTS
- LIST OF FIGURES
- LIST OF TABLES
- SECTION 1 – GENERAL CHILLER INFORMATION & SAFETY
- SECTION 2 – PRODUCT DESCRIPTION
- INTRODUCTION
- GENERAL SYSTEM DESCRIPTION
- HIGH AMBIENT KIT
- BUILDING AUTOMATION SYSTEM INTERFACE
- MILLENIUM CONTROL CENTER
- POWER PANEL
- ACCESSORIES AND OPTIONS
- UNIT COMPONENTS
- CONTROL / POWER PANEL COMPONENTS
- PRODUCT IDENTIFICATION NUMBER (PIN)
- BASIC UNIT NOMENCLATURE
- REFRIGERANT FLOW DIAGRAM
- PROCESS AND INSTRUMENTATION DIAGRAM
- SECTION 3 – HANDLING AND STORAGE
- SECTION 4 – INSTALLATION
- INSTALLATION CHECKLIST
- HANDLING
- INSPECTION
- LOCATION AND CLEARANCES
- SPRING ISOLATORS (OPTIONAL)
- COMPRESSOR MOUNTING
- REMOTE COOLER OPTION
- CHILLED LIQUID PIPING
- PIPEWORK ARRANGEMENT
- DUCT WORK CONNECTION
- WIRING
- COMPRESSOR HEATERS
- RELIEF VALVES
- HIGH PRESSURE CUTOUT
- SINGLE-POINT SUPPLY CONNECTION – TERMINAL BLOCK, NON-FUSED DISCONNECT SWITCH OR CIRCUIT BREAKER
- USER CONTROL WIRING INPUTS
- USER CONTROL WIRING OUTPUTS
- SECTION 5 – TECHNICAL DATA
- OPERATIONAL LIMITATIONS (ENGLISH)
- HEAT EXCHANGER FLOW, GPM
- PHYSICAL DATA (ENGLISH)
- ELECTRICAL DATA
- ELECTRICAL NOTES
- ELECTRICAL DATA W/O PUMPS
- ELECTRICAL DATA W/ PUMPS
- ELECTRICAL NOTES AND LEGEND
- WIRING DIAGRAMS
- DIMENSIONS (ENGLISH)
- TECHNICAL DATA – CLEARANCES
- WEIGHT DISTRIBUTION AND ISOLATOR MOUNTING POSITIONS
- ISOLATOR INFORMATION FOR UNITS SHIPPED ON OR AFTER JUNE 15, 2008
- ISOLATOR INFORMATION FOR UNITS SHIPPED BEFORE JUNE 15, 2008
- SLRS Seismic Isolator Specifications
- SLRS Seismic Isolator Installation and Adjustment
- One Inch Deflection Spring Isolator Cross-reference
- Installation of 1” Deflection Mounts
- Neoprene Isolator Cross-reference
- Two Inch Deflection, Seismic Spring IsolatorCross-reference - SLRS
- SLRS Seismic Isolator Installation and Adjustment
- SECTION 6 – COMMISSIONING
- SECTION 7 – UNIT CONTROLS
- SECTION 8 – UNIT OPERATION
- CAPACITY CONTROL
- SUCTION PRESSURE LIMIT CONTROLS
- DISCHARGE PRESSURE LIMIT CONTROLS
- LEAVING CHILLED LIQUID CONTROL
- LEAVING CHILLED LIQUID CONTROLOVERRIDE TO REDUCE CYCLING
- LEAVING CHILLED LIQUID SYSTEM LEAD/LAG AND COMPRESSOR SEQUENCING
- RETURN CHILLED LIQUID CONTROL
- RETURN CHILLLED LIQUID SYSTEM LEAD/LAG AND COMPRESSOR SEQUENCING
- ANTI-RECYCLE TIMER
- ANTI-COINCIDENCE TIMER
- EVAPORATOR PUMP CONTROL & YORK HYDRO KIT PUMP CONTROL
- EVAPORATOR HEATER CONTROL
- PUMPDOWN CONTROL
- STANDARD CONDENSER FAN CONTROL
- LOAD LIMITING
- COMPRESSOR RUN STATUS
- ALARM STATUS
- REMOTE BAS/EMS TEMPERATURE RESET USINGA VOLTAGE OR CURRENT SIGNAL
- SECTION 9 – SERVICE AND TROUBLESHOOTING
- SECTION 10 – MAINTENANCE
JOHNSON CONTROLS
110
FORM 150.72-NM1 (908)
Commissioning
CHECKING SUPERHEAT AND SUBCOOLING
The subcooling temperature of each system can be
calculated by recording the temperature of the liquid
line at the outlet of the condenser and subtracting it from
the liquid line saturation temperature at the liquid stop
valve (liquid line saturation temp. is converted from a
temperature/pressure chart).
Example:
Liquid line pressure =
325 PSIG converted to temp. 101 °F
minus liquid line temp. - 86 °F
Subcooling = 15 °F
The subcooling should be adjusted to 15 °F at design
conditions.
1. Record the liquid line pressure and its correspond-
ing temperature, liquid line temperature and
subcooling below:
SYS 1 SYS 2
Liq Line Press = _______ _______ PSIG
Saturated Temp = _______ _______ °F
Liq Line Temp = _______ _______ °F
Subcooling = _______ _______ °F
After the subcooling is veried, the suction superheat
should be checked. The superheat should be checked
only after steady state operation of the chiller has been
established, the leaving water temperature has been pulled
down to the required leaving water temperature, and the
unit is running in a fully loaded condition. Correct superheat
setting for a system is 10 °F – 15 °F (5.56 °C – 8.33 °C)
18” (46 cm) from the heat exchanger.
Superheat should typically be set for no less than 10
°F with only a single compressor running on a circuit.
The superheat is calculated as the difference between the
actual temperature of the returned refrigerant gas in the
suction line entering the compressor and the temperature
corresponding to the suction pressure as shown in a
standard pressure/temperature chart.
Example:
Suction Temp = 46 °F
minus Suction Press
105 PSIG converted to Temp - 34 °F
Superheat = 12 °F
When adjusting the expansion valve (TXV only), the
adjusting screw should be turned not more than one
turn at a time, allowing sufcient time (approximately
15 minutes) between adjustments for the system and the
thermal expansion valve to respond and stabilize.
Assure that superheat is set at a minimum of 10 °F (5.56
°C) with a single compressor running on each circuit.
2. Record the suction temperature, suction pressure,
suction saturation temperature, and superheat of
each system below:
SYS 1 SYS 2
Suction Temp = _______ _______ °F
Suction Pressure = _______ _______ PSIG
Saturation Temp = _______ _______ °F
Superheat = _______ _______ °F
LEAK CHECKING
1. Leak check compressors, ttings, and piping to
ensure no leaks.
If the unit is functioning satisfactorily during the initial
operating period, no safeties trip and the compressors
cycle to control water temperature to setpoint, the chiller
is ready to be placed into operation.