Table 32 - Troubleshooting - York YCAL Series Installation Operation & Maintenance

SECTION 9 - SERVICE AND TROUBLESHOOTING
TABLE 32 – TROUBLESHOOTING
PROBLEM
NO DISPLAY ON PANEL
UNIT WILL NOT OPERATE
FLOW SWITCH/REM
STOP NO RUN PERMISSIVE
LOW SUCTION PRESSURE FAULT
154
CAUSE
1. No 115VAC to 24 VAC Transformer IT.
2. No 24VAC to Microboard.
3. 1T defective, no 24VAC output.
4. Short in wire to temp. sensors or
pressure transducers.
5. Defective IPU & I/O board or Display
board.
1. No chilled liquid flow.
2. Flow switch improperly installed.
3. Defective flow switch.
4. Remote cycling device open.
1. Improper suction pressure cutouts
adjustments.
2. Low refrigerant charge.
3. Fouled filter dryer.
4. TXV defective.
5. Reduced flow of chilled liquid through
the cooler.
6. Defective suction pressure transducer/
low pressure switch or wiring.
7. LLSV defective.
FORM 150.66-NM3
ISSUE DATE: 09/25/2020
SOLUTION
1a. Check wiring and fuse 1FU.
1b. Check wiring emergency stop
contacts 5 to L of TB1 terminal
block.
1c. Replace 1T.
2. Check wiring 1T to Microboard.
3. Replace 1T.
4. Unplug connections at I/O board
to isolate.
5. Replace Microboard.
Contact Johnson
Controls Service
before replacing
circuit boards.
1. Check chilled liquid flow.
2. Check that the flow switch
is installed according to
manufacturer's instructions.
3. Replace flow switch.
4. Check cycling devices
connected to terminals 13 and
14 of the CTB1 terminal block.
1. Adjust per recommended
settings.
2. Repair leak if necessary and add
refrigerant.
3. Change dryer/core.
4. Replace TXV.
5. Check GPM (See "Limitations"
in "Installation" section). Check
operation of pump, clean pump
strainer, purge chilled liquid
system of air.
6. Replace transducer/low pressure
switch or faulty wiring. Refer to
"Service" section for pressure/
voltage formula.
7. Replace LLSV.
JOHNSON CONTROLS