Manitowoc QF0400 Service Manual

Also see for QC0700: Installation, use & care manual Service manual Building instructions Technician's handbook

Contents

Manitowoc QF0400 Service Manual Manual pdf 55 page image

Section 5 TroubleshootingPart No. 80-1214-3 5-3Analyzing Why SafeGuards May Stop theIce MachineAccording to the refrigeration industry, a highpercentage of compressor failure are the result ofexternal causes. These can include flooding or starvingexpansion valves, dirty condensers, water loss to the icemachine, etc. SafeGuards protect the ice machine(primarily the compressor) from external failures bystopping ice machine operation before major componentdamage occurs.Refrigeration and electrical component failures may alsotrip a safeguard. Eliminate all electrical components andexternal causes first. If it appears that the refrigerationsystem is causing the problem, use the charts,checklists, and other references to determine the cause.NOTE: The following checklists are designed to assistthe service technician in analysis. However, becausethere are many possible external problems, do not limityour diagnosis to only the items listed.SAFEGUARD MODESNo WaterDuring the Freeze cycle if the water level probe opens orremains open for more than 90 continuous seconds, theice machine will de-energize the compressor and gearmotor, continuously flash the water level light and initiatea 60 minute Standby Mode.During the Standby Mode the water level light willcontinually flash to indicate a Standby Mode.After the 60 -minute Standby Mode, the ice machine willde-energize the water level light and initiate a start-upsequence.WATER CONTACTS THE WATER LEVEL PROBE:The ice machine continues to make ice.WATER LEVEL PROBE OPENS OR REMAINS OPENFOR MORE THAN 90 CONTINUOUS SECONDS:The ice machine will start another 60-minute StandbyMode.The ice machine repeats the above sequence until:Water contacts the water level probeorThe toggle switch is moved to the OFF position.INDICATOR LIGHTBefore 48 hours have elapsed:After a Standby Mode has been initiated the water levellight will flash anytime the toggle switch is placed in theOFF position.After 48 hours have elapsed:The SafeGuard will be automatically erased frommemory and the water level will not flash.No Water ChecklistPossible Problem List Corrective Action ListNo water Restore water supply.Quick disconnect removed from water float valve Restore water supply.Water float valve screen blocked Clean screen.Water float valve solenoid coil defective Replace coil (see Water float valve diagnostics).Water float valve improperly adjusted Adjust valve (see Water level check).Dump valve leaking Repair or replace dump valve.Water level probes disconnected or removed Connect and correctly position probes.Revised 8/2003Downloaded from www.Manualslib.com manuals search engine