Hoshizaki FS-1022MLH-C service manual Diagnostic Charts, No Ice Production

F. Diagnostic Charts

Before consulting the diagnostic charts, check for correct installation, proper voltage per unit nameplate, and adequate water supply. Check CB using the steps in "IV.C. Control Board Check." Check that the S1 dip switch settings are in the factory default position. For factory default settings, see "II.C.3.a) Default Dip Switch Settings."

1. No Ice Production

No Ice Production - Possible Cause

	Startup
1a. Power Supply-FS	a) Unplugged, off, blown fuse, or tripped breaker.
	b) Not within specifications.
1b. Power Supply-SRC	a) Off, tripped breaker.
	b) Not within specifications.
2. Water Supply	a) Water supply off or improper water pressure.
	b) External water filters clogged.
3. Power Switch	a) "OFF" position.
4. Control Transformer	a) Coil winding open or shorted.
(115V/24V)
5. Fuse (Control Box)	a) Blown.
6. Control Board	a) In alarm.
See "IV.C. Control Board Check"
	b) BC OPEN, yellow LED on (bin full).
	c) Defective.
7. Control Switch	a) In "DRAIN" position.
	b) Bad contacts.
8. Infrared Sensor Bin Control	a) No power, lens dirty, or defective.
	b) Control board dip switch 7 off.
9. Mechanical Backup Bin Control	a) Tripped with bin filled with ice (9-beep alarm).
	b) Proximity switch stuck open.
	c) Actuator paddle does not move freely.
	Fill Cycle
1. Control Board	a) No power to inlet water valve.
	b) No power to float switch or not reading float switch condition.
2. Inlet Water Valve	a) Screen or orifice clogged.
	b) Coil winding open.
3. Float Switch	a) Float does not move freely.
See "IV.E. Float Switch Check
	b) Defective.
and Cleaning"
	Ice Purge Cycle
1. Control Board	a) No power to gear motor.
	b) No power to gear motor protect relay circuit.
2. Gear Motor	a) Blown fuse.
	b) Internal protector open.
	c) Gear motor winding open.
	d) Mechanical failure.

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