Problem: SYS # HIGH DSCH displayed (High discharge pressure trip) Check for voltage dip on compressor start.Check main supply is stable and within allowable limits.Problem: Chiller FAULT: VAC UNDERVOLTAGE displayed. Check the voltage to the unloader valve solenoid. Check that the compressor unloads correctly.Check for restrictions in the liquid fl ow line. Check that the liquid fl ow is stable.Leaving liquid drops below the programmed low limit faster than the unit can unload.Problem: Chiller FAULT: LOW WATER TEMP displayed Check fans are operating correctly and the rotation is correct.Check that the programmed settings are correct for the options fi tted to the unit.The warning message should clear when the ambient air temperature falls below the programmed operating limit. Use the ‘ambient temp.’ key to display the temperature and confi rm that the displayed value is approximately correct.Recirculated air is affecting the sensor.Ambient air temperature is higher than the programmed operating limit.Problem: Chiller FAULT: HIGH AMBIENT TEMP displayed Check the programmed settings are correct for the options fi tted to the unit.The warning message should clear when the ambient air temperature rises above the programmed operating limit Ambient air temperature is lower than the programmed operating limit.Problem: Chiller FAULT: LOW AMBIENT TEMP displayed Check for airfl ow restrictions caused by blockages on intake faces of air coils.Poor airfl ow through the condenser coils.Check that the fl ow switch is functional and is installed according to the manufacturer’s instructions. Check cycling contacts.Valves are correctly set and fl ow is established. Flow switch or cycling contacts are not made.

Problem: NO RUN PERM displayed (No run permissive) Replace powerboard or isolate excessive load on the board.Check wiring from – T2 to powerboard and fuse.Turn to ON position (1) if safe to do so. Check if control panel emergency stop switch and any remote emergency stop devices are in the OFF position.Switch on main supply if safe to do so.

York ycal parts