York YLUA0248 Series Installation Operation & Maintenance page 92

FORM 150.73-CL2
SECTION 6 – COMMISSIONING
ISSUE DATE: 10/29/2012
3. Program/verify the Cooling Setpoints, Program
Setpoints, and unit Options. Record the values
below. .................................................................
OPTIONS
Display Language
SYS 1 Switch
Sys 2 Switch
Chilled Liquid
* Ambient Control
Local/Remote Mode
Control Mode
Display Units
* Lead/Lag Control
* Fan Control
Manual Override
Current Feedback
** Soft Start
** Unit Type
** Refrigerant Type
** Expansion Valve Type
COOLING SETPOINTS
Cooling Setpoint
Range
EMS-PWM Max. Setpoint
PROGRAM
Discharge Pressure Cutout
Suct. Pressure Cutout
Low Amb. Temp. Cutout
Anti-Recycle Time
Fan Control On Pressure
Fan Differential Off Pressure
Total # of Compressors
* Number of Fans/System
* Unit/Sys Voltage
Unit ID
* Sys 1 Superheat Setpoint
* Sys 2 Superheat Setpoint
* Not On All Models
** Viewable Only
92
4. Put the unit into Service Mode (as described
under the Control Service and Troubleshooting
section) and cycle each condenser fan to ensure
proper rotation. ...................................................
5. Prior to this step, turn system 2 off (if applicable
–refer to YLUA - Installation, Operation,
Maintenance Manual (Form 150.73-NM1) Unit
Keys, Option 2 for more information on system
switches). Connect a manifold gauge to system
1 suction and discharge service valves. ............
Place the Unit Switch in the control panel
to the "ON" position. As each compressor
cycles on, ensure that the discharge pressure
rises and the suction pressure decreases. If
this does not occur, the compressor being
tested is operating in the reverse direction
and must be corrected. After verifying proper
compressor rotation, turn the Unit Switch to "OFF."
The discharge air or suction pressure
setpoint may need to be temporarily
lowered to ensure all compressors cycle
"on."
This unit uses scroll compressors
which can only operate in one direc-
tion. Failure to observe this will lead
to compressor failure.
6. Turn system 1 "off" and system 2 "on" (refer to
YLUA - Installation, Operation, Maintenance
Manual (Form 150.73-NM1) Unit Keys, Option 2
for more information on system switches). ........
Place the Unit Switch in the control panel to
the "ON" position. As each compressor cycles
"ON", ensure that the discharge pressure
rises and the suction pressure decreases. If
this does not occur, the compressor being
tested is operating in the reverse direction
and must be corrected. After verifying proper
compressor rotation, turn the Unit Switch to "OFF".
The chilled liquid setpoint may need
to be temporarily lowered to ensure all
compressors cycle "ON".
FORM 150.73-NM2
ISSUE DATE: 09/07/2020
JOHNSON CONTROLS