Hoshizaki American, Inc. KML-451MAH, KML-451MWH Service Manual

Hoshizaki America, Inc.

Hoshizaki

Low-Profile Modular Crescent Cuber

Models
KML-451MAH

“A Superior Degree

of Reliability”

www.hoshizaki.com

KML-451MWH

SERVICE MANUAL

™

Number: 73143
Issued: 3-1-2007

IMPORTANT

Only qualified service technicians should attempt to service or maintain this
unit. No such service or maintenance should be undertaken until the technician
has thoroughly read this Service Manual.

HOSHIZAKI provides this manual primarily to assist qualified service technicians in the
service and maintenance of the unit.

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

HOSHIZAKI AMERICA, INC.
618 Highway 74 South
Peachtree City, GA 30269

Attn: HOSHIZAKI Technical Support Department

Phone: [phone] Technical Service
[phone]
Fax: [phone]
[phone]
E-mail: [e-mail]

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

Please review this manual. It should be read carefully before the icemaker is serviced or
maintenance operations are performed. Only qualified service technicians should service
and maintain the icemaker. This manual should be made available to the technician prior to
service or maintenance.

CONTENTS

I. Specifications ...................................................................................................................... 5

A. Icemaker ....................................................................................................................... 5

1. KML-451MAH (air-cooled) ....................................................................................... 5

2. KML-451MWH (water-cooled) .................................................................................

II. General Information ........................................................................................................... 7

A. Construction .................................................................................................................. 7

1. KML-451MAH (air-cooled) ....................................................................................... 7

2. KML-451MWH (water-cooled) ................................................................................. 8

B. Sequence of Operation ................................................................................................. 9

1. One Minute Fill Cycle .............................................................................................. 9

2. Initial Harvest Cycle ................................................................................................ 9

3. Freeze Cycle ........................................................................................................... 9

4. Pump-Out Cycle ..................................................................................................... 9

5. Normal Harvest Cycle ............................................................................................ 9

C. Control Board .............................................................................................................. 11

1. Control Board Layout ............................................................................................. 12

2. Features ................................................................................................................ 13

a) Maximum Water Supply Period – 6 minutes ....................................................... 13

b) Harvest Backup Timer and Freeze Timer ........................................................... 13

c) High Temperature Safety .................................................................................... 13

d) Low Water Safety ............................................................................................... 13

e) High Voltage and Low Voltage Cut-outs ............................................................. 13

f) LED Lights and Audible Alarm Safeties ............................................................... 14

3. Controls and Adjustments ..................................................................................... 15

a) Default Dip Switch Settings ................................................................................ 15

b) Harvest Timer (dip switch 1 & 2) ........................................................................ 15

c) Pump-Out Timer (dip switch 3 & 4) ..................................................................... 16

d) Pump-Out Frequency Control (dip switch 5 & 6) ................................................ 16

e) Freeze Timer (dip switch 9 & 10) ........................................................................ 17

4. Control Board Check Procedure ............................................................................ 17

5. Control Board Replacement .................................................................................. 17

D. Harvest Control – Thermistor ...................................................................................... 18

E. Bin Control .................................................................................................................. 18

F. Switches ...................................................................................................................... 18

1. Control Switch ....................................................................................................... 18

2. Service Switch ....................................................................................................... 19

a) DRAIN ................................................................................................................ 19

b) CIRCULATE ....................................................................................................... 19

c) WASH ................................................................................................................. 19

6

3

III. Technical Information ...................................................................................................... 20

A. Water Circuit and Refrigeration Circuit ........................................................................ 20

1. KML-451MAH (air-cooled) ..................................................................................... 20

2. KML-451MWH (water-cooled) ...............................................................................

B. Wiring Diagrams .......................................................................................................... 22

1. KML-451MAH (air-cooled) and KML-451MWH (water-cooled) ............................. 22

C. Performance Data ....................................................................................................... 23

1. KML-451MAH (air-cooled) ..................................................................................... 23

2. KML-451MWH (water-cooled) ...............................................................................

IV. Service Diagnosis ........................................................................................................... 25

A. 10-Minute Diagnostic Procedure ................................................................................ 25

B. Diagnostic Charts ........................................................................................................ 26

1. No Ice Production .................................................................................................. 26

2. Evaporator is Frozen Up ........................................................................................

3. Low Ice Production ................................................................................................ 31

4. Abnormal Ice ......................................................................................................... 31

5. Other ...................................................................................................................... 31

V. Removal and Replacement of Components .................................................................... 33

A. Service for Refrigerant Lines ...................................................................................... 33

1. Refrigerant Recovery ............................................................................................. 33

2. Brazing .................................................................................................................. 33

3. Evacuation and Recharge (R-404A) ...................................................................... 34

B. Removal and Replacement of Compressor ................................................................ 35

C. Removal and Replacement of Expansion Valve ......................................................... 36

D. Removal and Replacement of Hot Gas Valve or Line Valve ....................................... 36

E. Removal and Replacement of Evaporator .................................................................. 37

F. Removal and Replacement of Water Regulating Valve - Water Cooled Model Only.... 38

G. Adjustment of Water Regulating Valve - Water-Cooled Model Only ........................... 39

H. Removal and Replacement of Headmaster (Condensing Pressure Regulator - C.P.R.)

- Remote Air-Cooled Model Only .............................................................................. 39

I. Removal and Replacement of Thermistor .................................................................... 40

J. Removal and Replacement of Fan Motor .................................................................... 41

K. Removal and Replacement of Water Valves ............................................................... 41

L. Removal and Replacement of Pump Motor ................................................................. 42

VI. Cleaning and Maintenance Instructions ......................................................................... 43

A. Cleaning and Sanitizing Procedures ........................................................................... 43

1. Cleaning Procedure ............................................................................................... 43

2. Sanitizing Procedure – Following Cleaning Procedure ..........................................

B. Maintenance ................................................................................................................ 45

C. Preparing the Icemaker for Long Storage ................................................................... 45

21

24

30

44

4

I. Specifications

AC SUPPLY VOLTAGE 115/60/1
AMPERAGE 10.3 A ( 5 Min. Freeze AT 104°F / WT 80°F)
MINIMUM CIRCUIT AMPACITY 20 A
MAXIMUM FUSE SIZE 20 A
APPROXIMATE ICE PRODUCTION Ambient WATER TEMP. (°F)
PER 24 HR. Temp.(°F) 50 70 90
lbs./day ( kg/day ) 70 *403 (183) 387 (176) 355 (161)
Reference without *marks 80 391 (177) 366 (166) 328 (149)

90 387 (176) *349 (158) 313 (142)

100 377 (171) 340 (154) 279 (127)
SHAPE OF ICE Crescent Cube
ICE PRODUCTION PER CYCLE 7.0 lbs. (3.2 kg) 360 pcs.
APPROXIMATE STORAGE CAPACITY N/A
ELECTRIC & WATER CONSUMPTION 90/70°F 70/50°F
ELECTRIC W (kWH/100 lbs.) 970(6.7) 890(5.3)
WATER gal./24HR (gal./100 lbs.) 64(18.3) 115(28.5)
EXTERIOR DIMENSIONS (WxDxH) 30" x 27 3/8" x 22" (762 x 695 x 560 mm)
EXTERIOR FINISH Stainless Steel, Galvanized Steel (Rear)
WEIGHT Net 154 lbs. (70 kg), Shipping 185 lbs. (84 kg)
CONNECTIONS - ELECTRIC Permanent - Connection

- WATER SUPPLY Inlet 1/2" FPT

- DRAIN Outlet 3/4" FPT
CUBE CONTROL SYSTEM Float Switch
HARVESTING CONTROL SYSTEM Hot Gas and Water, Thermistor and Timer
ICE MAKING WATER CONTROL Timer Controlled. Overflow Pipe
COOLING WATER CONTROL N/A
BIN CONTROL SYSTEM Thermostat
COMPRESSOR Hermetic, Model RS43C2E-CAA-219
CONDENSER Air-Cooled, Fin and tube type
EVAPORATOR Vertical type, Stainless Steel and Copper
REFRIGERANT CONTROL Thermostatic Expansion Valve
REFRIGERANT CHARGE R404A, 1 lb. 13.1 oz. (825g)
DESIGN PRESSURE High 467PSIG, Low 230PSIG
P.C. BOARD CIRCUIT PROTECTION High Voltage Cut-out ( Internal )
COMPRESSOR PROTECTION Auto-reset Overload Protector ( Internal )
REFRIGERANT CIRCUIT PROTECTION Auto-reset High Pressure Control Switch
LOW WATER PROTECTION Float Switch
ACCESSORIES -SUPPLIED N/A

-REQUIRED Ice Storage Bin
OPERATING CONDITIONS VOLTAGE RANGE 104 - 127 V

AMBIENT TEMP. 45 -100° F
WATER SUPPLY TEMP. 45 - 90° F
WATER SUPPLY PRESSURE 10 - 113 PSIG

A. Icemaker

1. KML-451MAH (air-cooled)

Note: We reserve the right to make changes in specifications and design without prior

notice.

5

2. KML-451MWH (water-cooled)

AC SUPPLY VOLTAGE 115/60/1
AMPERAGE 8.9 A ( 5 Min. Freeze AT 104°F / WT 80°F)
MINIMUM CIRCUIT AMPACITY 20 A
MAXIMUM FUSE SIZE 20 A
APPROXIMATE ICE PRODUCTION Ambient WATER TEMP. (°F)
PER 24 HR. Temp.(°F) 50 70 90
lbs./day ( kg/day ) 70 *404 (183) 402 (182) 384 (174)
Reference without *marks 80 402 (183) 399 (181) 373 (169)

90 402 (182) *397 (180) 374 (169)

100 393 (178) 392 (178) 352 (160)
SHAPE OF ICE Crescent Cube
ICE PRODUCTION PER CYCLE 6.8 lbs. (3.1 kg) 360 pcs.
APPROXIMATE STORAGE CAPACITY N/A
ELECTRIC & WATER CONSUMPTION 90/70°F 70/50°F
ELECTRIC W (kWH/100 lbs.) 880(5.3) 860(5.1)
WATER gal./24HR (gal./100 lbs.) 78(19.7) 125(31.0)
WATER COOLED CONDENSER 548(138) 319(79)

gal./24HR (gal./100 lbs.)
EXTERIOR DIMENSIONS (WxDxH) 30" x 27 3/8" x 22" (762 x 695 x 560 mm)
EXTERIOR FINISH Stainless Steel, Galvanized Steel (Rear)
WEIGHT Net 154 lbs. (70 kg), Shipping 185 lbs. (84 kg)
CONNECTIONS - ELECTRIC Permanent - Connection

- WATER SUPPLY Inlet 1/2" FPT Condenser Inlet 1/2" FPT

- DRAIN Outlet 3/4" FPT Condenser Outlet 3/8" FPT
CUBE CONTROL SYSTEM Float Switch
HARVESTING CONTROL SYSTEM Hot Gas and Water, Thermistor and Timer
ICE MAKING WATER CONTROL Timer Controlled. Overflow Pipe
COOLING WATER CONTROL Water Regulator
BIN CONTROL SYSTEM Thermostat
COMPRESSOR Hermetic, Model RS43C2E-CAA-219
CONDENSER Water-cooled, Tube in tube type
EVAPORATOR Vertical type, Stainless Steel and Copper
REFRIGERANT CONTROL Thermostatic Expansion Valve
REFRIGERANT CHARGE R-404A, 1 lb. 2.3 oz. (520g)
DESIGN PRESSURE High 427PSIG, Low 230PSIG
P.C. BOARD CIRCUIT PROTECTION High Voltage Cut-out ( Internal )
COMPRESSOR PROTECTION Auto-reset Overload Protector ( Internal )
REFRIGERANT CIRCUIT PROTECTION Auto-reset High Pressure Control Switch
LOW WATER PROTECTION Float Switch
ACCESSORIES -SUPPLIED N/A

-REQUIRED Ice Storage Bin
OPERATING CONDITIONS VOLTAGE RANGE 104 - 127 V

AMBIENT TEMP. 45 -100° F
WATER SUPPLY TEMP. 45 - 90° F
WATER SUPPLY PRESSURE 10 - 113 PSIG

Note: We reserve the right to make changes in specifications and design without prior

notice.

6

II. General Information

A. Construction

1. KML-451MAH (air-cooled)

Spray Tubes

Drain Valve

Wash Valve

Inlet Water
Valve

Water Supply
Inlet

Condenser
Fan Motor

Junction Box

Condenser

Water Pump

Float Switch

Expansion
Valve

Control
Switches

Control Box

Drier

Hot Gas Valve

Compressor

Bin Control
Thermostat

7

2. KML-451MWH (water-cooled)

Water Supply
Inlet

Spray Tubes

Drain Valve

Water
Regulator

Wash Valve

Inlet Water
Valve

Water Pump

Float Switch

Junction Box

Condenser

Control Box

Drier

Expansion
Valve

Control
Switches

Hot Gas Valve

Compressor

Bin Control
Thermostat

8

B. Sequence of Operation

The steps in the sequence are as outlined below. When power is supplied, a 5 second
delay occurs at startup. Note that the order of the LEDs from the outer edge of the board
is 1, 4, 3, 2.

1. One Minute Fill Cycle

LED 4 is on. WV opens and the fill period begins. After 1 minute, the board checks for
a closed F/S. If F/S is closed, the harvest cycle begins. If not, WV will remain energized
through additional 1 minute cycles until water enters the sump and F/S closes. This
serves as a low water safety to protect the water pump.

2. Initial Harvest Cycle

LEDs 1, 4, and 2 are on. WV remains open, Comp and FMR energize, HGV opens,
and harvest begins. As the evaporator warms, the thermistor located on the suction line
checks for a 48°F (9°C) temperature. When 48°F (9°C) is reached, a 3.9 kΩ signal turns
the harvest over to the adjustable harvest timer which is factory set for normal conditions.
The timer has settings of 60, 90, 120, and 180 seconds (dip switch 1 & 2). The water
valve is open during harvest for a maximum of 6 minutes or the length of harvest,
whichever is shorter. When the harvest timer completes its count down, the harvest cycle
is complete and the freeze cycle starts.The minimum total time allowed by the board for
a complete harvest cycle is 2 minutes.

3. Freeze Cycle

LED 1 is on. Comp and FMR continue to run, PM and FMS energize, LLV opens, HGV
and WV close and the freeze cycle starts. For the first 5 minutes the control board
will not accept a signal from F/S. This 5 minute minimum freeze acts as a short cycle
protection. At the end of 5 minutes, F/S assumes control. As ice builds on the evaporator
the water level in the sump lowers. The freeze continues until F/S opens and terminates
ice production.

4. Pump-Out Cycle

LEDs 1, 3, and 2 are on. Comp and FMR continue to run, HGV opens, LLV closes, and
FMS de-energizes. PM stops for 2 seconds. SR energizes, restarting PM and taking
water from the sump and forcing it to go through DV and down the drain. When the
pump-out timer stops counting, the pump out is complete.
Pump out always occurs on the 2nd harvest after startup. Then, depending on the control
board setting, pump out occurs every cycle, or every 2nd, 5th or 10th cycle (dip switch
5 & 6).

5. Normal Harvest Cycle

LEDs 1, 4, and 2 are on. Comp and FMR continue to run, HGV remains open and WV
opens. As the evaporator warms, the thermistor reaches 48°F (9°C). The control board
then receives the thermistor's 3.9 kΩ signal and starts the harvest timer. The water valve
is open during harvest for a maximum of 6 minutes or the length of harvest, whichever is
shorter. When the harvest timer completes its count down, the harvest cycle is complete
and the next freeze cycle starts. The unit continues to cycle through 3, 4 and 5 sequence
until the bin control senses ice and shuts the unit down.

Legend: Comp–compressor; DV–Drain Valve; FMR–remote fan motor; FMS–self-contained

fan motor; F/S–float switch; HGV–hot gas valve; LLV–Liquid Line Valve; PM–pump

motor; SR–Service Relay; WV–inlet water valve

9

Cycle

4. Pump-Out

F/S in

control

5 minute timer

in control

• Minimum freeze time: 5 minutes

• Maximum freeze time: freeze timer setting

1 to 3 minute timer

in control

F/S closed

F/S Check

PM stops for 2 sec., SR

energizes, starting PM &

DV for 10/20 sec. each 1,

2, 5, or 10 cycles.

Freeze cycle

operation turned

over to F/S

Comp continues

FMR continues

HGV de-energized

WV de-energized

Thermistor temp

reaches 48°F (9°C)

(3.9 kΩ or less)

Harvest timer starts

Comp continues

PM energized

FMR continues

HGV energized

FMS energized

LLV energized

F/S open

FMS de-energized

LLV de-energized

Power is supplied to the pump and drain valve. This drains the water tank.

Power is supplied to the pump only. This operation can be used to circulate cleaner for

extended periods of time over the outside surface of the evaporator.

Power is supplied to the pump and wash valve. This operation is used to circulate cleaner

and sanitizer over both the inside and outside surfaces of the evaporator.

2. Harvest Cycle 3. Freeze Cycle

Thermistor in

• Maximum harvest time: 20 minutes

Fill Cycle

control

F/S closed

F/S Check

Comp energized

WV Energized

HGV energized

FMR energized

WV continues

F/S open

• Maximum inlet water valve time: 6 minutes

1. One Minute

KML-451MAH and KML-451MWH Sequence Flow Chart and Component Operation

Cycle Steps

"E" board will have

Initial startup always

5 second delay

begins here

LLV de-energized

10

If F/S is open, compressor stops and cycle returns to 1 minute fill

Legend:

Comp–compressor

DV–drain valve

FMR–remote fan motor

Components Energized when the Control Switch is in the SERVICE Position

When in the "SERVICE" position, the control switch supplies power to the service switch and the machine

is in service mode. The service switch has three positions: "DRAIN," "CIRCULATE" and "WASH." See the

information below for details of each function.

FMS–self-contained fan motor

F/S–float switch

HGV–hot gas valve

LLV–liquid line valve

PM–pump motor

SR–service relay

DRAIN

CIRCULATE

WV–inlet water valve

WASH

C. Control Board

• A HOSHIZAKI exclusive solid-state control is employed in KML-451MAH and
KML-451MWH Modular Crescent Cubers.

• All models are pretested and factory-adjusted.

CAUTION

1. Fragile, handle very carefully.

2. A control board contains integrated circuits, which are susceptible to failure
due to static discharge. It is especially important to touch the metal part of
the unit when handling or replacing the board.

3. Do not touch the electronic devices on the board or the back of the board to
prevent damage to the board.

4. Do not change wiring and connections. Do not misconnect K3, K4 and K5,
because the same connector is used for the thermistor and float switch. K4 is
not connected.

5. Always replace the whole board assembly if it goes bad.

6. Do not short out power supply to test for voltage.

11

1. Control Board Layout

Control Products "E" Control Board

Alarm Reset Switch

Backup Freeze
Timer LED

Backup Harvest
Timer LED

Alarm Buzzer

Dip Switch

Output Test Switch
(used to test relays on board)

Connector K3
Harvest Control
(thermistor)

Connector K4
Open
(not connected)

Power LED
(lights when
power is supplied
to the board)

Relay LEDs (4)
(indicate which
relays are energized
as listed below)

LED 2
Hot Gas Valve (HGV)
Self-Contained Fan
Motor (FMS) (FMS
off when LED on)

LED 3
Pump Motor (PM)
(on at pump out only)

LED 4
Water Valve (WV)

LED 1
Compressor (Comp)
Remote Fan Motor
(FMR)

Transformer
Connector

Microprocessor
(board revision level
indicated by last 2
digits on label)

Connector K5
Float Switch

Part Number

Connector K1

Pins #1 through #10
#1, 9 Magnetic Contactor
#2 Hot Gas Valve
#3 Line Valve
Self-Contained Fan Motor (FMS)
#4 Pump Motor (icemaking)
#5 Pump Motor (drain)
#6 Water Valve
#7, 10 Power (line, bin control)
#8 Open

Switch for "C" board
and "ALPINE" board
(service boards only)

Control Board

Part Number 2A1410-01 (factory); 2A1410-02 (service)

Type HOS-001A (Control Products - 10 Pin)

12

2. Features

a) Maximum Water Supply Period – 6 minutes

Inlet water valve opening, in the harvest cycle, is limited by the harvest timer. The water
valve cannot remain open longer than the maximum period. The water valve can close in
less than six minutes if the harvest cycle is completed.

b) Harvest Backup Timer and Freeze Timer

The harvest backup timer shuts down the icemaker if, for two cycles in a row, the harvest
cycle takes more than 20 minutes to complete. The control board will signal this problem
using 2 beeps every 3 seconds.
The freeze timer shuts down the icemaker if, for two cycles in a row, the freeze cycle
takes longer than the time specified to complete. The control board will signal this
problem using 3 beeps every 3 seconds. The time is factory set using dip switches 9 &

10.
The reset button on the control board must be pressed with power on to reset either of
these safeties.

c) High Temperature Safety

The temperature of the suction line in the refrigeration circuit is limited by the high
temperature safety. This protects the unit from excessively high temperatures. If the
evaporator temperature rises above 127°F ± 7°F (53°C ± 4°C), the thermistor operates
the safety. This shuts down the circuit and the icemaker automatically stops.
The control board will signal this problem using 1 beep every 3 seconds. The reset button
on the control board must be pressed with power on to reset the safety.

d) Low Water Safety

The control board checks the position of the float switch at the end of the initial one
minute water fill cycle and at the end of each harvest cycle.
If the float switch is in the up position (electrical circuit closed), the control board changes
to the next cycle. If the float switch is in the down position (electrical circuit open), the
control board changes to additional one minute water fill cycles until water enters the
sump and the float switch closes. When the float switch closes, the control board changes
to the next cycle. The unit will not start without adequate water in the sump. This serves
as a low water safety to protect the water pump.
For water-cooled model, if the condenser water supply is shut off, the unit is protected by
the high-pressure switch.

e) High Voltage and Low Voltage Cut-outs

The maximum and minimum allowable supply voltages of this icemaker are limited by the
high voltage and low voltage cut-outs.
If miswiring (especially on single phase 3 wire models) causes excessive voltage (147Vac
±5% or more) on the control board, the high voltage cut-out shuts down the circuit
in 3 seconds and the icemaker automatically stops. The control board will signal this
problem using 7 beeps every 3 seconds.
The icemaker also automatically stops in cases of insufficient voltage (92Vac ±5% or
less). The control board will signal this problem using 6 beeps every 3 seconds.
When the proper supply voltage is resumed, the icemaker automatically starts running
again.

13

f) LED Lights and Audible Alarm Safeties

The red LED indicates proper control voltage and will remain on unless a control voltage
problem occurs. At startup a 5 second delay occurs while the board conducts an internal
timer check. A short beep occurs when the power switch is turned OFF.
The green LEDs 1 through 4 energize and sequence from initial startup as listed in the
table below. Note that the order of the LEDs from the outer edge of the board is 1, 4, 3, 2.
For more information, see "II.B. Sequence of Operation."

Sequence Step LED

1 Minute Fill Cycle 4 WV 60 seconds
Harvest Cycle 1, 4, and 2 WV, HGV,

Freeze Cycle 1 Comp, PM,

Pump Out 1, 3, and 2 Comp, HGV,

The built in safeties shut down the unit and have alarms as follows:

No. of Beeps

(every 3 sec.)

1 High Evaporator Temp.

(temperature > 127°F)
(53°C)

2 Harvest Backup Timer

(harvest > 20 min. for two
cycles in a row)

Type of Alarm Notes

Energized

Components

Comp, FMR

FMR/FMS,
LLV

PM, FMR,
SR, DV

Min. Max. Avg.

2 minutes 20 minutes 3 to 5 minutes

5 minutes freeze timer

10 seconds 20 seconds factory setting

Check for harvest problem (stuck HGV or
relay), hot water entering unit, stuck HM,
or shorted thermistor.

Orange LED marked H TIMER lights up.
Check for open thermistor, HGV not
opening, TXV leaking by, low charge, or
inefficient compressor.

Time LEDs are On

30 to 35 minutes

setting

3 Freeze Timer

(freeze > specified setting
for two cycles in a row)
Timer is factory set using
dip switches 9 & 10

To manually reset the above safeties, press the alarm reset button with the power
supply on.

6 Low Voltage

(92Vac ±5% or less)

7 High Voltage

(147Vac ±5% or more)

Legend: Comp–compressor; DV–Drain Valve; FMR–remote fan motor; FMS–self-
contained fan motor; F/S–float switch; HGV–hot gas valve; HM–headmaster
(C.P.R.); LLV–Liquid Line Valve; PM–pump motor; SR–Service Relay;
TXV–thermostatic expansion valve; WV–inlet water valve

Yellow LED marked F TIMER lights up.
Check for F/S stuck closed (up), WV
leaking by, HGV leaking by, TXV not
feeding properly, low charge, HM not
bypassing, or inefficient compressor.

Red LED will turn off if voltage protection
operates.
The control voltage safeties automatically
reset when voltage is corrected.

14