Shut down on
maximum harvest time
Ice bridge thickness too small,
not enough ice to open curtain
Check and adjust if needed
Ice bridge thickness too large,
ice frozen to evaporator frame
Check and adjust if needed
Purge valve does not open,
water melts ice bridge, not
enough ice to open curtain
Check purge valve
Incomplete ice formation
Check water distributor for
partially plugged holes
Curtain out of position
Check curtain for swing
restriction
Curtain switch does not open
when curtain does
Check switch with ohmmeter
Machine in very cold ambient
Move machine to a warmer
location
Hot gas valve does not open
Check hot gas valve, check
controller using test mode
Harvest assist probe out of
position – ejector pin not
retracted
Check harvest assist
mechanism – spring should
retract pin
Damaged evaporator
Check evaporator surface
Fan motor stays on during
harvest
Check controller using test
mode
Shut down on
minimum freeze time
Grounded ice thickness sensor
Check sensor for dirt and
position. Clean and check gap
to evaporator surface.
September 2006 Page 44
Diagnostics – Air Cooled
Problem
Likely Cause
Probable Solution
