York YCAL0066 Installation Operation & Maintenance

JOHNSON CONTROLS
186
FORM 150.67-NM2
ISSUE DATE: 01/31/2019
SECTION 9 – SERVICE AND TROUBLESHOOTING
TROUBLESHOOTING
TABLE 37 - TROUBLESHOOTING
PROBLEM CAUSE SOLUTION
No display on panel.
Unit will not operate.
1. No 115VAC to 24 VAC Transformer
2. No 24VAC to Microboard
3. Control Transformer defective, no
24VAC output.
4. Short in wire to temp. sensors or
pressure transducers.
5. Defective IPU II & I/O Board or the
Display Board.
1a. Check wiring and fuse 1FU
b. Check wiring emergency stop con-
tacts 5 to L of TB1 Terminal Block.
c. Replace Control Transformer
2. Check wiring Control Transformer to
Microboard.
3. Replace Control Transformer
4. Unplug connections at IPU II & I/O
Board to isolate.
5. Replace IPU II & I/O Board or the
Display Board.
Contact YORK Service
before replacing circuit
boards!
“Flow Switch/REM Stop No Run
Permissive”
1. No chilled liquid ow.
2. Flow switch improperly installed.
3. Defective ow switch.
4. Remote cycling device open.
1. Check chilled liquid ow.
2. Check that the ow switch is installed
according to manufacturer’s instruc-
tions.
3. Replace ow switch.
4. Check cycling devices connected
to terminals 13 and 14 of the CTB1
terminal Block.
“Low Suction Pressure” Fault 1. Improper suction pressure cutouts
adjustments.
2. Low refrigerant charge.
3. Fouled lter dryer.
4. TXV defective.
5. Reduced ow of chilled.
6. Defective suction pressure transduc-
er/low pressure switch or wiring.
7. LLSV defective.
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” liquid
through the cooler in installation sec-
tion). 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
“High Discharge Pressure” Fault 1. Condenser fans not operating or
operating backwards.
2. Too much refrigerant.
3. Air in refrigerant system.
4. Defective discharge pressure trans-
ducer.
1. Check fan motor, and contactors. As-
sure fan blows air upward.
2. Remove refrigerant.
3. Evacuate and recharge system.
4. Replace discharge pressure trans-
ducer. Refer to service section for
pressure/voltage formula.

York YCAL0066 Specifications

General

Brand	York
Model	YCAL0066
Category	Chiller
Language	English