York YVAA Installation Operation & Maintenance page 180

SECTION 9 - MAINTENANCE
Table 32 - Troubleshooting guide (cont'd)
Problem
System status:
Motor current limiting
VSD fault:
High baseplate temperature
VSD fault:
Low DC Bus voltage
Note: Always remove power to the chiller and ensure the DC Bus voltage has bled off.
180
Possible cause
A high motor current anticipatory control
has activated current limiting
Coolant level low.
Glycol pump is defective.
VSD Board is defective.
IBGT Module is defective.
VSD cooling coil not clean.
SCR/Diode Module is defective.
SCR Trigger Board is defective.
Form 201.47-ICOM1
Issue date: 17/11/2022
Action
Ambient temperature is high, normal
response from controller
Remote or panel limiting is in effect,
Normal response.
Excess charge in system, adjust charge.
Condenser coils dirty, Clean condenser.
Fans not operating. Check fans.
Add coolant.
Replace Glycol Pump.
Replace VSD Logic Board.
Check defective IGBT Module.
Clean VSD cooling coil.
Check SCR/Diode Module.
Check SCR Trigger Board.
JOHNSON CONTROLS