Hoshizaki KM660MRJ, KM520MRJ, KM520MAJ, KM350MWJ User Manual

Service Manual

Modular Crescent Cuber

Models KM-350MAJ, MWJ

KM-520MAJ, MWJ, MRJ KM-660MAJ, MWJ, MRJ

					hoshizakiamerica.com	Number: 73230
						Issued: 8-3-2018

WARNING

Only qualified service technicians should install and service the appliance. To obtain the name and phone number of your local Hoshizaki Certified Service

Representative, visit www.hoshizaki.com. No service should be undertaken until the technician has thoroughly read this Service Manual. Failure to service and maintain the appliance in accordance with this manual will adversely affect safety, performance, component life, and warranty coverage. Proper installation is the responsibility of the installer. Product failure or property damage due to improper installation is not covered under warranty.

Hoshizaki provides this manual primarily to assist qualified service technicians in the service of the appliance.

Should the reader have any questions or concerns which have not been satisfactorily addressed, please call, send an e-mail message, or write to the Hoshizaki Technical Support Department for assistance.

Phone: [phone]

Fax: [phone]

E-mail: [e-mail]

618 Highway 74 South

Peachtree City, GA 30269

Attn: Hoshizaki Technical Support Department

Web Site: www.hoshizaki.com

NOTE: To expedite assistance, all correspondence/communication MUST include the following information:

•Model Number

•Serial Number

•Complete and detailed explanation of the problem.

2

IMPORTANT
This manual should be read carefully before the appliance is serviced. Read
the warnings and guidelines contained in this manual carefully as they provide
essential information for the continued safe use, service, and maintenance of the
appliance. Retain this manual for any further reference that may be necessary.
CONTENTS
Important Safety Information..................................................................................................	5
I. Construction and Water/Refrigeration Circuit Diagram........................................................	7
A. Construction...................................................................................................................	7
1. Air-Cooled Models (MAJ)..........................................................................................	7
2. Water-Cooled Models (MWJ)...................................................................................	8
3. Remote Models (MRJ).............................................................................................	9
B. Water/Refrigeration Circuit Diagram............................................................................	10
1. Air-Cooled Models (MAJ)........................................................................................	10
2. Water-Cooled Models (MWJ)..................................................................................	11
3. Remote Models (MRJ)...........................................................................................	12
II. Sequence of Operation and Service Diagnosis................................................................	13
A. Sequence of Operation Flow Chart.............................................................................	13
1. Operation Flow Chart ............................................................................................	13
2. Shutdown Flow Chart.............................................................................................	14
3. Freeze-Time Correction Chart................................................................................	15
B. Service Diagnosis........................................................................................................	16
C. Freeze-Time Correction Cycle (90 min.)......................................................................	22
D. Control Board Check....................................................................................................	24
E. Bin Control Check and Adjustment..............................................................................	25
F. Float Switch Check and Cleaning.................................................................................	28
G. Thermistor Check........................................................................................................	30
H. Control Switch..............................................................................................................	30
I. Mode Switch..................................................................................................................	30
J. Diagnostic Tables..........................................................................................................	31
K. Freeze-Up Check List..................................................................................................	35
III. Controls and Adjustments................................................................................................	36
A. Control Board Layout...................................................................................................	37
B. LED Lights and Audible Alarm Safeties.......................................................................	38
C. Settings and Adjustments............................................................................................	39
1. Default Dip Switch Settings.....................................................................................	39
2. Harvest Time (S4 dip switch 1 & 2)........................................................................	40
3. Pump-Out Time/Harvest Time During Pump-Out (S4 dip switch 3 & 4).................	40
4. Pump-Out Frequency Control (S4 dip switch 5).....................................................	41
5. Harvest Pump Time (Harvest Assist) (S4 dip switch 6)..........................................	41
6. Harvest Pump Time (Harvest Assist)/Freeze-Time Correction (S4 dip switch 7)...	42
7. Factory Use (S4 dip switch 8).................................................................................	42
8. Freeze Timer (S4 dip switch 9 & 10).......................................................................	43
9. Pump-Out Pump Motor Direction (S5 dip switch 1)................................................	43
10. Refill Counter (S5 dip switch 2 and 3)..................................................................	44
11. Minimum Harvest Time (S5 dip switch 4)..............................................................	44
12. Anti-Slush (S5 dip switch 5)..................................................................................	44

3

IV. Refrigeration Circuit and Component Service Information..............................................	45
A. Refrigeration Circuit Service Information.....................................................................	45
B. Component Service Information..................................................................................	48
C. Water Regulating Valve Adjustment (water-cooled model)...........................................	49
V. Maintenance.....................................................................................................................	50
VI. Preparing the Appliance for Periods of Non-Use.............................................................	51
VII. Disposal.........................................................................................................................	53
VIII. Technical Information....................................................................................................	54
A. Specification and Performance Data Sheets...............................................................	54
1. KM-350MAJ............................................................................................................	54
2. KM-350MWJ..........................................................................................................	55
3. KM-520MAJ...........................................................................................................	56
4. KM-520MWJ..........................................................................................................	57
5. KM-520MRJ with URC-5F......................................................................................	58
6. KM-660MAJ...........................................................................................................	59
7. KM-660MWJ...........................................................................................................	60
8. KM-660MRJ with URC-5F......................................................................................	61
B. Wiring Diagrams .........................................................................................................	62
1. KM-350M_J, KM-520M_J, KM-660M_J..................................................................	62

4

Important Safety Information

Throughout this manual, notices appear to bring your attention to situations which could result in death, serious injury, damage to the appliance, or damage to property.

WARNING	Indicates a hazardous situation which could result in death or
	serious injury.
NOTICE	Indicates a situation which could result in damage to the
	appliance or property.
IMPORTANT	Indicates important information about the use and care of the
	appliance.

WARNING

The appliance should be destined only to the use for which it has been expressly conceived. Any other use should be considered improper and therefore dangerous. The manufacturer cannot be held responsible for injury or damage resulting from improper, incorrect, and unreasonable use. Failure to service and maintain the appliance in accordance with this manual will adversely affect safety, performance, component life, and warranty coverage and may result in costly water damage.

To reduce the risk of death, electric shock, serious injury, or fire, follow basic precautions including the following:

•Only qualified service technicians should install and service this appliance.

•The appliance must be installed in accordance with applicable national, state, and local codes and regulations.

•Electrical connection must be hard-wired and must meet national, state, and local electrical code requirements. Failure to meet these code requirements could result in death, electric shock, serious injury, fire, or severe damage to equipment.

•The icemaker requires an independent power supply of proper capacity. See the

nameplate for electrical specifications. Failure to use an independent power supply of proper capacity can result in a tripped breaker, blown fuses, damage to existing wiring, or component failure. This could lead to heat generation or fire.

•THE ICEMAKER MUST BE GROUNDED. Failure to properly ground the icemaker could result in death or serious injury.

•Move the control switch to the "OFF" position and turn off the power supply before servicing. Lockout/Tagout to prevent the power supply from being turned back on inadvertently.

•To reduce the risk of electric shock, do not touch the control switch with damp hands.

•Do not make any alterations to the unit. Alterations could result in electric shock, injury, fire, or damage to the unit.

•The appliance is not intended for use by persons (including children) with reduced physical, sensory, or mental capabilities, or lack of experience and knowledge, unless they have been given supervision or instruction concerning use of the appliance by a person responsible for their safety.

5

WARNING, continued

•Children should be properly supervised around this appliance.

•Do not climb, stand, or hang on the appliance or allow children or animals to do so.

Serious injury could occur or the appliance could be damaged.

•Do not use combustible spray or place volatile or flammable substances near the appliance. They might catch fire.

•Keep the area around the appliance clean. Dirt, dust, or insects in the appliance could cause harm to individuals or damage to the appliance.

Additional Warning for Remote Models

•THE REMOTE CONDENSER UNIT MUST BE GROUNDED. The power supply and ground connection to the remote condenser unit are supplied from the icemaker.

Failure to properly ground the remote condenser unit could result in death or serious injury.

•Move the icemaker control switch to the "OFF" position and turn off the power supply to the icemaker before servicing the remote condenser unit.

Lockout/Tagout to prevent the power supply from being turned back on inadvertently.

NOTICE

•Follow the instructions in this manual carefully to reduce the risk of costly water damage.

•In areas where water damage is a concern, install in a contained area with a floor drain.

•Install the appliance in a location that stays above freezing. Normal operating ambient temperature must be within 45°F to 100°F (7°C to 38°C).

•Do not leave the icemaker on during extended periods of non-use, extended absences, or in sub-freezing temperatures. To properly prepare the icemaker for these occasions, follow the instructions in "VI. Preparing the Appliance for Periods of Non-Use."

•Do not place objects on top of the appliance.

•The dispenser unit/ice storage bin is for ice use only. Do not store anything else in the dispenser unit/ice storage bin.

6

I. Construction and Water/Refrigeration Circuit Diagram

A. Construction

1. Air-Cooled Models (MAJ)

Drain Valve

Cleaning Valve

Spray Tubes

Evaporator

Inlet Water Valve

Thermostatic

Expansion Valve

Float Switch

Compressor

Water Pump

Control Switch

Mode Switch

Water Supply Inlet

Stainer

Hot Gas Valve

Condenser

High-Pressure

Switch

Fan Motor

Liquid Line

Valve

Drier

Bin

Control

Control Box

Model Shown: KM-350MAJ

7

2. Water-Cooled Models (MWJ)

Drain Valve

		Water Supply Inlet
	Cleaning Valve
	Spray Tubes
	Inlet Water Valve
		Stainer
	Evaporator	Hot Gas Valve
		Water Regulating
		Valve
	Thermostatic	High-Pressure Switch
	Expansion
	Valve	Condenser
		Drier
	Float Switch
	Water Pump	Liquid Line Valve
		Bin Control
	Compressor
	Control Switch	Control Box
	Mode Switch
		Model Shown: KM-520MWJ

8

3. Remote Models (MRJ)

	Drain Valve	Thermostatic
		Expansion Valve
	Spray Tubes
		Water Supply Inlet
	Cleaning Valve
	Inlet Water Valve
	Evaporator

Stainer

Hot Gas Valve

Receiver Tank

High-Pressure

Switch

Drier

Float Switch

Liquid Line Valve

Water Pump

Bin Control

Crankcase Heater

Compressor

Control Switch

Control Box

Mode Switch

Model Shown: KM-660MRJ

9

10

		Spray Tubes			.B
				(MAJ)ModelsCooled-Air.1	CircuitWater/Refrigeration
			Condenser
	Evaporator	Inlet Water Valve
		Water Supply
			Fan
			Drier
			Liquid Line Valve
		Cleaning Valve	Heat
			Exchanger		Diagram
		Drain Valve		High-Pressure
		Thermistor
				Switch
			Suction Line
				Strainer
		Float Switch		Hot Gas
		Water Tank
				Valve
			Discharge Line
			Compressor
Drain		Water Pump
			Thermostatic Expansion Valve
		Refrigeration Circuit
		Water Circuit

		Water Regulating Valve
		Spray Tubes	.2
			-Water
		Inlet Water Valve
	Evaporator		Cooled
		Condenser
		Water Supply	Models
		Drier
		Cleaning Valve
		Liquid Line Valve	(MWJ)
		Heat
		Exchanger
		Drain Valve
	11	Thermistor	High-Pressure
		Suction Line	Switch
			Strainer
		Float Switch	Hot Gas
		Water Tank	Valve
		Compressor Discharge Line
	Drain	Water Pump
		Thermostatic Expansion Valve
		Refrigeration Circuit
		Water Circuit

12

Headmaster (C.P.R.)

Fan

Spray Tubes

Remote Condenser

Evaporator	Inlet Water Valve
	Water Supply
	Cleaning Valve
	Drain Valve
	Thermistor

Float Switch

Water Tank

Drain

Water Pump

Receiver

Liquid Line				Drier
Valve

Heat

Exchanger

High-Pressure

Switch

Suction Line

Strainer

Hot Gas

Valve

Compressor Discharge Line

Thermostatic Expansion

Valve

(MRJ) Models Remote .3

Refrigeration Circuit

Water Circuit

Operation Flow Chart

.1

1. 1-Minute

Operation

Cycle

2. Harvest Cycle

3. Freeze Cycle

4. Pump-Out Cycle

Steps

Fill Cycle

• WV time: 6 min. or the length of harvest minus 50 sec.

• Min. freeze time: 5 min.

• Factory set for every 10th

(S4 dip switch 7), whichever is shorter. Do not adjust S4

• Max. freeze time: freeze timer setting (S4 dip

cycle

dip switch 7 out of the factory position.

switch 9 & 10)

(S4 dip switch 5)

Flow

• Max. harvest time: 20 min.

• Freeze-Time monitoring for Freeze-Time

• Pump motor stops for

Correction starts at 2nd freeze cycle.

2 sec., then reverses for

10/20 sec.

Chart

Thermistor

1 to 3-min. harvest timer in

5-min.

(S4 dip switch 3 & 4)

in control

control (S4 dip switch 1 & 2)

minimum

FS in control

Harvest Pump

freeze timer in

control

Timer

FS opens or freeze

timer terminates

Startup

50 sec.

FS closed

FS closed

FS check

PM energized

FS check

WV energized

Comp energized

WV de-energized

Comp energized

Anti-Slush

Comp energized

Thermistor temperature reaches

FMR energized

FM energized

Thermistor temperature

DV energized

48°F (9°C) (3.9 kΩ or less).

FS open

HGV energized

FMR energized

reaches 36°F (2.2°C)

FMR energized

Harvest timer starts.

13

WV energized

PM energized

(5.8 kΩ).

HGV energized

LLV energized

PM de-energized for

PM de-energizes for 2 sec.,

FS open

HGV de-energized

10 sec.

then energizes for 10/20 sec.

FM de-energized

LLV de-energized

If FS is open, Comp stops and cycle returns to

1-Min. fill.

Legend: BC–bin control

Comp–compressor

DV–drain valve FM–fan motor

FMR–fan motor-remote FS–float switch HGV–hot gas valve

LLV–liquid line valve PM–pump motor

WV–inlet water valve

Freeze Time Differential Exceeded.

Initiate Freeze-Time Correction Cycle.

See "II.A.3. Freeze-Time Correction Cycle.

Components Energized when the Control Switch is in the "PUMP" Position

When the control switch is in the "PUMP" position power is supplied to the pump motor. Water tank contents then flows over the outside of the evaporator plate assembly. Note: Water tank contents does not flow inbetween the evaporator plates.

Components Energized when the Control Switch is in the "ON" or "PUMP" position and the Mode Switch is in the "CLEAN" Position

•When the control switch is in the "ON" position and the mode switch is in the "CLEAN" position power is supplied to the control board K9 connector. The control board then initiates a clean/sanitze program. See the maintenance label on the top cover or the instruction manual for details.

•When the control switch is in the "PUMP" position and the mode switch is in the "CLEAN" position, only the pump motor energizes and circulates water tank contents over outside of evaporator plate assembly as the control board power supply has been disconnected. The Clean/Sanitize program cannot initiate in this scenario.

Chart Flow Operation of Sequence .A	Service and Operation of Sequence .II
	Diagnosis

14

Shutdown Flow Chart

Shutdown					1. Bin Full	2. Icemaker Off	3. Ice Level Lowered
and Restart					Shutdown Delay:	All components	Icemaker starts at
					• Fill Cycle–15 sec. after activation.	de-energized.	"1. 1-Minute Fill Cycle."
					• Harvest Cycle–At the end of the harvest cycle, or up
					to 15 sec. into the freeze cycle if
					activated at the end of the harvest cycle.
					• Freeze Cycle– 15 sec. after activation if activated at least
					15 sec. before the 5-min. short cycle
					protection timer terminates.
					Otherwise, at the end of the next harvest
					cycle.
BC Operation								To 1. 1-Minute Fill Cycle

BC open (BC sensor engaged)

Green UBC LED off Yellow "BC OPEN" LED on

Legend:

BC–bin control

Yellow "BC OPEN" LED continues. All	BC closed
components de energized.	(BC sensor disengaged)
	Green UBC LED on
	Yellow "BC OPEN" LED off

Control board retains freeze-time correction count data between bin control restarts.

Chart Flow Shutdown .2

15

Freeze Time Differential Exceeded. Minimum and Maximum Recorded Freeze times have exceeded 600 sec. (10 min.)

Freeze-Time Correction function is enabled when S4 Dip Switch 7 is in the "ON" position and initiates when the difference between the minimum and maximum recorded freeze times is equal to or greater than 600 sec.

(10 min.).

Freeze time is recorded and freeze cycles are counted starting at the 2nd freeze cycle after startup from a power off condition. After 6 recorded freeze cycles, CB starts comparing the minimum and maximum differential of recorded freeze cycle times.

Up to 10 freeze cycles are recorded and maintained in memory. At the 11th recorded freeze cycle, the first recorded freeze

cycle time is dropped to maintain the maximum number of 10 recorded freeze cycles.

Note: When 1st freeze-time correction cycle is initiated, CB "POWER OK" LED starts blinking. On 2nd freeze-time correction cycle, if CB "POWER OK" LED has been reset, CB "POWER OK" LED starts blinking. If CB

"POWER OK" had not been reset after 1st freeze-time correction cycle CB "POWER OK" LED continues to blink.

After 3rd freeze time correction cycle in

36 hours, CB yellow "EXT HARVEST" LED starts blinking.

Appliance continues to operate and LEDs continue to blink until ALARM RESET button is pressed with power on.

	2A8242-01 Freeze-Time Correction Flow Chart								-Freeze .3
									Time
Cycle Steps					1. 10-Minute Harvest Cycle with WV		2. 10-Minute Fill/
									Correction
Freeze Time Correction						• Do not adjust S4 dip switch 7 out of the factory position.	Overflow
Steps 1 and 2 repeat
4 times (total 80 min.),						• After step 2 completes 4th sequence (80 min. completed), repeat
then step 1 repeats for						step 1 for 5th and final time.
a 5th time to complete
Cycle.									Chart
	Start

Comp energized

FMR energized

HGV energized

PM energized

WV energized

Legend:

Comp–compressor

FM–fan motor

FMR–fan motor-remote

HGV–hot gas valve

PM–pump motor

WV–inlet water valve

Appliance Cycle Reset and Alarm Reset:

Cycle Reset: Power Supply or Control Switch Turned Off and On again: Appliance turns off, then re-starts at 1.Fill Cycle.

Alarm Reset: CB "ALARM RESET" pressed during or after a freeze-time correction cycle with power supply on:

Appliance continues cycle with no interruption or reset.

CB red "POWER OK" LED blinking:

CB red "POWER OK" LED resets to solid.

CB yellow "EXT HARVEST" LED blinking:

CB yellow "EXT HARVEST: LED turns off.

WV energized

Comp de-energized

FMR de-energized

HGV de-energized

PM de-energized

After 5th 10-Minute Harvest Pump Cycle with WV Freeze-Time Correction Cycle Complete.

Go to Step "3. Freeze Cycle" in Operation Flow Chart.

B. Service Diagnosis

WARNING

•The appliance should be diagnosed and repaired only by qualified service personnel to reduce the risk of death, electric shock, serious injury, or fire.

•Risk of electric shock. Control switch in "OFF" position does not de energize all loads Use extreme caution and exercise safe electrical practices.

•Moving parts (e.g., fan blade) can crush and cut. Keep hands clear.

•Before servicing the appliance, move the control switch to the "OFF" position and turn off the power supply.

•CHOKING HAZARD: Ensure all components, fasteners, and thumbscrews are securely in place after the appliance is serviced. Make sure that none have fallen into the dispenser unit/ice storage bin.

•Make sure all food zones in the appliance and dispenser unit/ice storage bin are clean after service.

The diagnostic procedure is a sequence check that allows you to diagnose the electrical system and components. Before proceeding, check for correct installation, proper voltage per nameplate, and adequate water supply. Check CB using the steps in "II.D. Control Board Check." Check dip switch settings to assure that S4 dip switches and S5 dip switches 1 through 5 are in the factory default position. S4 dip switch 1, 2, 3, 4, and 5 are cleaning adjustments and the settings are flexible. For factory default settings, see "III.C.1. Default Dip Switch Settings."

Note: • When checking high voltage (115VAC), always choose a white (W) neutral wire to establish a good neutral connection.

•When checking voltage from the CB K1 connector (10 pin connector), pull CB K1 connector out slightly to allow room for multimeter test leads contact.

1)Turn off the power supply, then access the control box. Move the control switch to the "OFF" position. Clear ice from BC sensing area.

2)Check that the 115VAC 10A fuse is good.

16

1.Sequence and Component Diagnosis

3)Power On: Turn on the power supply, then move the control switch to the "ON"

position and the mode switch to the "ICE" position. A 5 sec. delay occurs. CB red

"POWER OK" LED turns on. If CB yellow "BC OPEN" LED is on (indicating a full bin), move ice away from BC sensing area.

Note: • CB red "POWER OK" LED remains on unless the 10.5VAC power supply is interrupted (K2 connector).

•Check CB using the steps in "II.D. Control Board Check" or BC using steps in "II.E. Bin Control Check and Adjustment."

a)Power On Diagnosis: If CB red "POWER OK" LED is off, confirm 10A fuse is good.

Check for 115VAC at control switch #2 (BK) to neutral (W) then at control switch #1 (P) to neutral (W). If 115VAC is present on #2 (BK) and not on #1 (P), replace control switch. If 115VAC is present on control switch #1 (P), check for 115VAC at HPS (P)

to neutral (W) then HPS (BK) to neutral (W). If 115VAC is present at HPS (P) and not at HPS (BK), HPS is open. See HPS Diagnosis below. If 115VAC is present at HPS (BK), check for 10.5VAC at CB K2 #1 red wire to CB K2 #2 red wire. If 10.5VAC is not present, check that the cleaning valve is closed and the interlock switch is closed. Next, check CT continuity. If open, replace CT.

b)HPS Diagnosis: Check that the condenser coil is not clogged or restricted. Let refrigeration circuit pressures equalize. If HPS does not reset and pressures are equalized, replace HPS. If pressures are not equalized, reclaim refrigerant and diagnose refrigeration circuit restriction. Check that there are no restrictions in the refrigeration circuit.

Harvest Cycle: HGV, strainer, or check valve.

Freeze Cycle: FM, FMR, TXV, WRV, HM, LLV, strainer, check valve, drier, and damaged line set or fitting.

Confirm that the location meets installation requirements:

•The appliance is not intended for outdoor use. Normal operating ambient temperature should be within 45°F to 100°F (7°C to 38°C).

•Allow 6" (15 cm) clearance at rear, sides, and top for proper air circulation and ease of maintenance and/or service should they be required.

•The appliance should not be located in a corrosive environment.

4)1-Min. Fill Cycle – LED 4 is on. WV energizes. After 1 min., CB checks for a closed

FS. If FS is closed, the harvest cycle begins. If harvest cycle begins (Comp, HGV, FMR energized), continue to step 5a. If FS is open, WV remains energized until FS closes (low water safety protection during initial start up and at the end of each harvest). Diagnosis:

Check that water enters the water tank. If not, check that the water supply line shut-off valve is open and screens or external filters are clear. Check for 115VAC at CB K1 #6

(O) to neutral (W). If 115VAC is not present, replace CB. If 115VAC is present, and WV does not energize, check for 115VAC at WV. If 115VAC is present, check coil continuity.

If open, replace WV. If the water tank fills, but the appliance fails to start harvest (Comp energized), check for open FS. See "II.F. Float Switch Check and Cleaning." If FS is closed and CB fails to start the harvest cycle after 1 min., replace CB.

17

5a) Initial Harvest Cycle – LEDs 1, 4, and 2 are on. WV continues. Comp, FMR, and HGV energize. CB monitors the warming of the evaporator via the thermistor located on the suction line. When the thermistor reaches 48°F (9°C), CB reads 3.9 kΩ from the thermistor and turns harvest termination over to the harvest timer (S4 dip switch 1 & 2 and S5 dip switch 4). WV are energized during harvest for a maximum of 6 min. or the length of harvest minus HPT setting (S4 dip switch 6), whichever is shorter. See step 5b below.

a)Comp Diagnosis: Check that evaporator is warming. If not, confirm that Comp energizes. If not, check for 115VAC at CB K1 #9 (Y) to neutral (W). If 115VAC is not present, check for 115VAC at CB K1 #10 (BK) to neutral (W). If 115VAC is present at #10 (BK) and not at #9 (Y), replace CB. If 115VAC is present, check for 115VAC at mode switch #2 (Y) to neutral and mode switch #1 (V) to neutral. If 115VAC is present at #2 (Y) and not at #1 (V), confirm mode switch is in "ICE" position. If in

"ICE" position, check mode switch continuity. If open, replace mode switch. If 115VAC is present at mode switch #1 (V), check for 115VAC at CR solenoid. If 115VAC­ is present, confirm contacts are closed. If not, replace CR. If CR contacts are closed, check Comp external overload, Comp start and run capacitors, Comp start relay, and

Comp motor winding.

b)HGV Diagnosis: If Comp is energized and evaporator is not warming, check that HGV energizes and opens. Check for 115VAC at CB K1 #2 (P) to neutral (W).

If 115VAC is not present, check for 115VAC at CB K1 #1 (V). If 115VAC is not present, check wiring for loose connection from CB 10 pin connector pin #1 (V) to mode switch. If 115VAC is present on #1 (V) and not at #2 (Y), replace CB.

If 115VAC is present at #2 (Y), check for 115VAC at HGV coil and check HGV coil continuity. Replace as needed. Note: LED is off when HGV is energized and on when

LLV/FM are energized.

c)LLV Diagnosis: Confirm that LLV is de-energized and closed (not bypassing).

If energized, replace CB. If de-energized and bypassing, replace LLV.

d)WRV Diagnosis: Confirm WRV is not leaking by. If WRV is leaking by, confirm HGV is open and LLV is closed. Next, check for proper refrigerant pressures. If refrigerant pressures are correct, adjust or replace WRV. See "IV.C. Water Regulating Valve

Adjustment (water cooled models).".

5b) Harvest Pump Time (Harvest Assist) – LEDs 1 and 3 are on. When the thermistor reaches 48°F (9°C), CB reads 3.9 kΩ from the thermistor and turns harvest termination over to the harvest timer (S4 dip switch 1 & 2 and S5 dip switch 4).

When WV de-energizes, LED 4 turns off and LED 3 turns on. PM energizes. Comp, FMR, and HGV continue.

Diagnosis: Place a thermometer on the suction line next to the thermistor. Has it warmed to 48°F (9°C) or warmer? Confirm thermistor status. See "II.G Thermistor

Check." If the thermistor reading is in proper range, dip switch 7 is on, and PM does not energize before harvest terminates, replace CB. If WV continues, check for 115VAC at

CB K1 #6 (O). If 115VAC is present, and LED 4 is off, replace CB. If LED 3 is on and PM is not energized, check for 115VAC at CB K1 #4 (R). If 115VAC is not present, replace

CB. If 115VAC is present and PM is not energized, check PM capacitor and motor winding continuity.

18

5c) Initial Harvest Cycle Termination Diagnosis: When the thermistor reaches 48°F (9°C), CB reads 3.9 kΩ from the thermistor and turns harvest termination over to the harvest timer (S4 dip switch 1 & 2 and S5 dip switch 4). Check discharge line temperature. For a thermistor check, see "II.G. Thermistor Check." If 1-min. fill cycle

starts after harvest timer terminates, check that FS is clean and operating properly, see "II.F. Float Switch Check and Cleaning." If FS is closed, CB proceeds to the next cycle. If not, replace CB.

Note: The minimum total time allowed by CB for a complete harvest cycle is based on

S5 dip switch 4. Maximum harvest time allowed is 20 min.

NOTICE! S4 dip switch 7 must remain on. Otherwise, PM will not energize during the last seconds of harvest.

6) Freeze Cycle – LED 1, 2, and 3 are on. Comp, FMR, and PM continue. FM and LLV energize. HGV de energizes. Appliance is held in freeze by a 5-min. short cycle protection timer. After 5-min. short cycle protection timer terminates and FS opens, freeze cycle terminates.

Note: PM power supply continues from CB K1 #4 (R) in harvest and in freeze. Anti-Slush: When anti-slush is enabled (S5 dip switch 5 "ON"), PM de-energizes when thermistor reaches 36°F (2.2°C) (5.8 kΩ) for 10 sec. then, energizes for the remainder of the freeze cycle.

a)Freeze Cycle Diagnosis: Confirm Comp, FMR, and PM continue. Confirm that FM and LLV energize. Confirm WRV opens. Next, confirm HGV de-energizes.

During the first 5 min. of freeze, confirm evaporator is cooling. If not, confirm

WV de-energized (not leaking by), HGV de-energized (not bypassing), LLV and FM energize, TXV and HM operate correctly, WRV opens, Comp is efficient, and refrigerant charge is correct. See "VIII.A. Specification and Performance Data Sheets."

b)Comp and FMR Diagnosis: If Comp and FMR de-energize once freeze begins, check that appliance has not shut off on HPS (CB "POWER OK" LED off). If so, check "3)b) HPS Diagnosis" above. If CB "POWER OK" LED is on, check for 115VAC at CB K1 #9 (Y) to neutral (W). If 115VAC is not present and LED 1 is on, replace CB. If 115VAC is present, check for 115VAC at CR coil. If 115VAC is present, check CR coil and contact continuity. Replace as needed. If CR is okay, check Comp start relay and start and run capacitors. Next, check Comp motor winding continuity. If Comp is energized but evaporator is not cooling, check for an inefficient Comp.

See "VIII.A. Specification and Performance Data Sheets." If Comp is energized but

FMR is not, check for 115VAC at the FMR junction box. If 115VAC is not present, check icemaker wiring connections. If 115VAC is present, check for voltage at condenser unit. If 115VAC is not present, check field wiring connections. If 115VAC is present, check FMR capacitor, motor winding, and fan blade for binding.

c)WV and HGV Diagnosis: If WV is energized, check for 115VAC at CB K1 #6 (O)

to neutral (W). If 115VAC is present after PM energizes in harvest cycle, replace CB. If 115VAC is not present, replace WV (bypassing). If HGV did not de energize at the end of harvest, check for 115VAC at CB K1 #2 (P) to neutral (W). If 115VAC is present and LED 2 is on, replace CB. If 115VAC is not present, replace HGV (bypassing).

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