Evacuating A System - York YCAV0569 Installation Operation & Maintenance

MAINTENANCE
(Always remove power to the chiller and assure the DC bus voltage has bled off)
PROBLEM
System Fault:
MOTOR
CURRENT
LIMITING
VSD Fault:
High
Baseplate
Temperature
VSD Fault:
Low DC
Bus Voltage

EVACUATING A SYSTEM

If a system or a portion of a system needs to be evacuat-
ed, it should be evacuated to a minimum of 500 microns.
The system should then be able to hold the vacuum for
10 minutes with a maximum rise of 50 microns. If the
system is not able to hold a vacuum, recheck the system
for leaks.
264
TROUBLESHOOTING GUIDE (CON'T)
POSSIBLE CAUSE
High motor current
has activated
current limiting
Coolant level low.
Glycol Pump is defective.
VSD Board is defective
IBGT Module is defective.
SCR / Diode Module
is defective.
SCR Trigger Board is defective.
FORM 201.21-NM2 (616)
ACTION
Ambient temperature is high,
normal response from controller
Remore or panel limiting is in
effect, Normal response.
Excess charge in system,
adjust charge.
Condensor coils dirty,
Clean condensor.
Fans NOT operating,
Check fans.
Add coolant.
Replace Glycol Pump.
Replace VSD Logic Board.
Check defective IGBT Module.
Check SCR / Diode Module.
Check SCR Trigger board.
JOHNSON CONTROLS