Scotsman AC-EC 57, AC-EC 47, AC-EC 127, AC-EC 87, AC-EC 177 Service Manual

...

Page 1

Scotsman Ice Srl Via Lainate, 31 - 20010 Pogliano M.se - Milano - Italy Tel. +39-02-93960.1 (Aut. Sel.)- Telefax +39-02-93550500 Direct Line to Service & Parts: Phone +39-02-93960350 - Fax +39-02-93540449 Website: www.scotsman-ice.it E-Mail: scotsman.europe@scotsman.it

ISO 9001 - Cert. n. 0080

AC-EC 47 AC-EC 57

AC-EC 87 AC-EC 107 AC-EC 127 AC-EC 177

R 290 version

Electronic cubers with storage

PC Board version

REV. 10/2018

SERVICE MANUAL

Page 2

INDICE

2 3 6

9 12 15 17

19 19 19 19 20 20 21

Table of contents page Specifications AC-EC 47 Specifications AC-EC 57 Specifications AC-EC 87 Specifications AC-EC 107 Specifications AC-EC 127 Specifications AC-EC 177

GENERAL INFORMATION AND INSTALLATION

Introduction Unpacking and Inspection Location and levelling Electrical connections Water supply and drain connections Final check list Installation practice

OPERATING INSTRUCTIONS

Start up Operational checks

OPERATING PRINCIPLES (How it works)

Freezing cycle Harvest cycle Electrical sequence Components description

ADJUSTMENT, REMOVAL AND REPLACEMENT PROCEDURES

Adjustment of the cube size Wiring diagram AC-EC 47-57-87-107-177 Service diagnosis

MAINTENANCE AND CLEANING INSTRUCTIONS

General Icemaker Clean - Replace of air condenser filter Cleaning instructions of water system

39 40 42

22 23

28 30 31 34

45 45 45 46

Page 3

Important operating requirements:

Air temperature Water temperature Water pressure Electr. voltage variations from voltage rating specified on nameplate

MIN. 10°C 5°C 1 bar

-10%

°C °F

SPECIFICATIONS

CUBER MODEL AC-EC 47

NOTE

. With the unit in "built-in" conditions, the ice production is gradually reduced in respect to the levels shown in the graf, up to a maximum of 10% at room temperatures higher than 32°C. The daily ice-making capacity is directly related to the condenser air inlet temperature, water temperature conditions of the condenser air filter and age of the machine.

To keep your SCOTSMAN CUBER at peak performance levels, periodic maintenance checks must be carried out as indicated on Maintenance and Cleaning section of this manual.

MAX. 40°C 35°C 5 bar

+10%

ice making capacity

24.5 24

23.5 23

22.5 22

21.5 21

20.5 20

19.5 19

18.5 18

17.5 17

16.5 16

15.5 15

14.5

Kg.

32 27 21 15 10

AIR COOLED MODELS

WA TER TEMPERATURE

AMBIENT TEMPERATURE

ICE PRODUCED PER 24 HRS.

°C

Page 4

AC 47 AS 6 Air AC 47 WS 6 Water

Stainless steel 1/4 9 Kg.

Start . Electric power cons.

Amps Kwh per 24 Hr

Model Cond. unit Finish Comp. HP

SPECIFICATIONS

Basic electr. Amps Watts Nr. of wires Amps fuse

230/50/1 2.1 12 400 3 x 1.5 mm

NYA

AC 47 - CUBER

machine specifications

Cubes per harvest: 18 medium * At 32/21 °C amb.-water

96**

NYA

Bin Water req. Capacity lt/24 HR

Page 5

Stainless steel 1/4 9 Kg.

Start . Electric power cons.

Amps Kwh per 24 Hr

Model Cond. unit Finish Comp. HP

SPECIFICATIONS

Basic electr. Amps Watts Nr. of wires Amps fuse

230/50/1 2.1 12 400 3 x 1.5 mm

NYA

Cubes per harvest: 18 medium * At 32/21 °C amb.-water

96**

NYA

Bin Water req. Capacity lt/24 HR

EC 47 AS 6 Air EC 47 WS 6 Water

EC 47 - CUBER

machine specifications

643

Page 6

MIN. 10°C 5°C

1 bar

-10%

Important operating requirements:

Air temperature Water temperature Water pressure Electr. voltage variations from voltage rating specified on nameplate

SPECIFICATIONS

CUBER MODEL AC-EC 57

MAX. 40°C 35°C 5 bar

+10%

ice making capacity

NOTE

To keep your SCOTSMAN CUBER at peak performance levels, periodic maintenance checks must be carried out as indicated on Maintenance and Cleaning section of this manual.

34 33 32 31 30 29 28 27 26 25 24 23 22 21 20 19 18

Kg.

32 27 21 15 10

AIR COOLED MODELS

WA TER TEMPERATURE

AMBIENT TEMPERATURE

ICE PRODUCED PER 24 HRS.

°C

Page 7

AC 57 AS 6 Air AC 57 WS 6 Water

Stainless steel 1/4 12.5 Kg.

Start . Electric power cons.

Amps Kwh per 24 Hr

Model Cond. unit Finish Comp. HP

SPECIFICATIONS

Basic electr. Amps Watts Nr. of wires Amps fuse

230/50/1 2.1 12 400 3 x 1.5 mm

0 96* **

NYA

AC 57 - CUBER

machine specifications

Cubes per harvest: 24 medium * At 32/21 °C amb.-water

7.6

NYA

Bin Water req. Capacity lt/24 HR

Page 8

Stainless steel 1/4 12.5 Kg.

Start . Electric power cons.

Amps Kwh per 24 Hr

Model Cond. unit Finish Comp. HP

SPECIFICATIONS

Basic electr. Amps Watts Nr. of wires Amps fuse

230/50/1 2.1 12 400 3 x 1.5 mm

0 96* **

NYA

EC 57 - CUBER

machine specifications

Cubes per harvest: 24 medium * At 32/21 °C amb.-water

7.6

NYA

Bin Water req. Capacity lt/24 HR

EC 57 AS 6 Air EC 57 WS 6 Water

Page 9

MIN. 10°C 5°C

1 bar

-10%

Important operating requirements:

Air temperature Water temperature Water pressure Electr. voltage variations from voltage rating specified on nameplate

SPECIFICATIONS

CUBER MODEL AC-EC 87

MAX. 40°C 35°C 5 bar

+10%

ice making capacity

NOTE

To keep your SCOTSMAN CUBER at peak performance levels, periodic maintenance checks must be carried out as indicated on Maintenance and Cleaning section of this manual.

44 43 42 41 40 39 38 37 36 35 34 33 32 31 30 29

Kg.

32 27 21 15 10

AIR COOLED MODELS

WA TER TEMPERATURE

AMBIENT TEMPERATURE

ICE PRODUCED PER 24 HRS.

10 21

°C

Page 10

AC 87 AS 6 Air AC 87 WS 6 Water

Stainless steel 1/3 19 Kg.

Start . Electric power cons.

Amps Kwh per 24 Hr

Model Cond. unit Finish Comp. HP

SPECIFICATIONS

Basic electr. Amps Watts Nr. of wires Amps fuse

230/50/1 3.2 20 570 3 x 1.5 mm

0143*

*NYA

AC 87 - CUBER

machine specifications

Cubes per harvest: 24 medium * At 32/21 °C amb.-water

10.8

NYA

Bin Water req. Capacity lt/24 HR

Page 11

EC 87 AS 6 Air EC 87 WS 6 Water

Stainless steel 1/3 19 Kg.

Start . Electric power cons.

Amps Kwh per 24 Hr

Model Cond. unit Finish Comp. HP

SPECIFICATIONS

Basic electr. Amps Watts Nr. of wires Amps fuse

230/50/1 3.2 20 570 3 x 1.5 mm

0143*

*NYA

EC 87 - CUBER

machine specifications

Cubes per harvest: 24 medium * At 32/21 °C amb.-water

10.8 NYA

Bin Water req. Capacity lt/24 HR

Page 12

MIN. 10°C 5°C 1 bar

-10%

Important operating requirements:

Air temperature Water temperature Water pressure Electr. voltage variations from voltage rating specified on nameplate

SPECIFICATIONS

ELECTRONIC CUBER MODEL AC-EC 107

MAX. 40°C 35°C 5 bar

+10%

ice making capacity

NOTE

To keep your SCOTSMAN CUBER at peak performance levels, periodic maintenance checks must be carried out as indicated on Maintenance and Cleaning section of this manual.

53 52 51 50 49 48 47 46 45 44 43 42 41 40 39 38

Kg.

32 27 21 15 10

AIR COOLED MODELS

WA TER TEMPERATURE

AMBIENT TEMPERATURE

ICE PRODUCED PER 24 HRS.

°C

Page 13

AC 107 AS 6 Air AC 107 WS 6 Water

Stainless steel 1/3 23 Kg.

Start . Electric power cons.

Amps Kwh per 24 Hr

Model Cond. unit Finish Comp. HP

SPECIFICATIONS

Basic electr. Amps Watts Nr. of wires Amps fuse

230/50/1 3.2 20 580 3 x 1.5 mm

0125* *NYA

AC 107 - CUBER (R290 version)

machine specifications

Cubes per harvest: 32 medium * At 32/21 °C amb.-water

10.7 NYA

Bin Water req. Capacity lt/24 HR

Page 14

Stainless steel 1/3 23 Kg.

Start . Electric power cons.

Amps Kwh per 24 Hr

Model Cond. unit Finish Comp. HP

SPECIFICATIONS

Basic electr. Amps Watts Nr. of wires Amps fuse

230/50/1 3.2 20 580 3 x 1.5 mm

0125* *NYA

EC 107 - CUBER (R290 version)

machine specifications

Cubes per harvest: 32 medium * At 32/21 °C amb.-water

10.7 NYA

Bin Water req. Capacity lt/24 HR

EC 107 AS 6 Air EC 107 WS 6 Water

Page 15

MIN. 10°C 5°C 1 bar

-10%

Important operating requirements:

Air temperature Water temperature Water pressure Electr. voltage variations from voltage rating specified on nameplate

SPECIFICATIONS

ELECTRONIC CUBER MODEL AC-EC 127

MAX. 40°C 35°C 5 bar

+10%

ice making capacity

NOTE

. With the unit in "built-in" conditions, the ice production is gradually reduced in respect to the levels shown in the graf, up to a maximum of 10% at room temperatures higher than 32

C. The daily ice-making capacity is directly related to the condenser air inlet temperature, water temperature conditions of the condenser air filter and age of the machine.

To keep your SCOTSMAN CUBER at peak performance levels, periodic maintenance checks must be carried out as indicated on Maintenance and Cleaning section of this manual.

Kg.

32 27 21 15 10

AIR COOLED MODELS

WATER TEMPERATURE

AMBIENT TEMPERATURE

ICE PRODUCED PER 24 HRS.

10 21

°C

Page 16

AC-EC 127 AS 6 Air AC-EC 127 WS 6 Water

Stainless steel 1/2 39 Kg.

Start . Electric power cons.

Amps Kwh per 24 Hr

Model Cond. unit Finish Comp. HP

SPECIFICATIONS

Basic electr. Amps Watts Nr. of wires Amps fuse

230/50/1 4.5 20.5 670 3 x 1.5 mm

177**

AC-EC 127 - CUBER

machine specifications

Cubes per harvest: 56 medium * At 21°C water temperature

Dimensions: HEIGHT (without legs) 920 mm.

HEIGHT (with legs) 1009 mm. WIDTH 680 mm. DEPTH 600 mm. WEIGHT 70 Kgs.

12.9.0

Bin Water req. Capacity lt/24 HR

920

Page 17

MIN. 10°C 5°C 1 bar

-10%

Important operating requirements:

Air temperature Water temperature Water pressure Electr. voltage variations from voltage rating specified on nameplate

SPECIFICATIONS

ELECTRONIC CUBER MODEL AC-EC 177

MAX. 40°C 35°C 5 bar

+10%

ice making capacity

NOTE

To keep your SCOTSMAN CUBER at peak performance levels, periodic maintenance checks must be carried out as indicated on Maintenance and Cleaning section of this manual.

97 96 95 94 93 92 91 90 89 88 87 86 85 84 83 82 81 80 79 78 77 76 75 74 73 72 71 70 69 68 67

Kg.

32 27 21 15 10

AIR COOLED MODELS

WA TER TEMPERATURE

AMBIENT TEMPERATURE

ICE PRODUCED PER 24 HRS.

10 21

°C

Page 18

Stainless steel 3/4 48 Kg.

AC-EC 177 AS 6 Air AC-EC 177 WS 6 Water

Start . Electric power cons.

Amps Kwh per 24 Hr

Model Cond. unit Finish Comp. HP

SPECIFICATIONS

Basic electr. Amps Watts Nr. of wires Amps fuse

230/50/1 4 22 1000 3 x 1.5 mm

150**

AC-EC 177 - CUBER

machine specifications

Cubes per harvest: 56 medium * At 21°C water temperature

Dimensions: HEIGHT (without legs) 990 mm.

HEIGHT (with legs) 1079 mm. WIDTH 680 mm. DEPTH 600 mm. WEIGHT 70 Kgs.

17.4.0

Bin Water req. Capacity lt/24 HR

Page 19

Forward the completed self-addressed registration card to Frimont factory.

11. If necessary, replace the four standard legs with the taller ones supplied in the machine and adjust them to level the unit.

C. LOCATION AND LEVELLING

WARNING. This Ice Cuber is designed for indoor installation only. Extended periods of operation at temperatures exceeding the following limitations will constitute misuse under the terms of the SCOTSMAN Manufacturer’s Limited Warranty resulting in LOSS of warranty coverage.

1. Position the unit in the selected permanent location. Criteria for selection of location include:

a) Minimum room temperature 10°C (50°F)

and maximum room temperature 40°C (100°F).

b) Water inlet temperatures: minimum 5°C

(40°F) and maximum 35°C (90°F).

c) Well ventilated location for air cooled

models.

d) Service access: adequate space must be left for all service connections through the rear of the ice maker. A minimum clearance of 15 cm (6") must be left at the sides of the unit for routing cooling air drawn into and exhausted out of the compartment to maintain proper condensing operation of air cooled models.

2. Level the unit in both the left to right and front to rear directions.

D. ELECTRICAL CONNECTIONS

See data plate for current requirements to determine wire size to be used for electrical connections. All SCOTSMAN icemakers require a solid earth wire. All SCOTSMAN ice machines are supplied from the factory completely pre-wired and require only electrical power connections to the wire cord provided at rear of the unit. Make sure that the ice machine is connected to its own circuit and individually fused (see data plate for fuse size). The maximum allowable voltage variation should not exceed -10% and + 10% of the data plate rating. Low voltage can cause faulty functioning and may be responsible for serious damage to the overload switch and motor windings.

NOTE.

All external wiring should conform to national, state and local standards and regulations.

A. INTRODUCTION

This manual provides the specifications and the step-by-step procedures for the installation, startup and operation, maintenance and cleaning for the SCOTSMAN AC-EC series icemakers. These Cubers are quality designed, engineered and manufactured. Their ice making systems are thoroughly tested providing the utmost in flexibility to fit the needs of a particular user. These icemakers have been engineered to our own rigid safety and performance standards.

NOTE

. To retain the safety and performance built into this icemaker, it is important that installation and maintenance be conducted in the manner outlined in this manual.

B. UNPACKING AND INSPECTION

1. Call your authorized SCOTSMAN Distributor or Dealer for proper installation.

Visually inspect the exterior of the packing and skid. Any severe damage noted should be reported to the delivering carrier and a concealed damage claim form filled in subjet to inspection of the contents with the carrier’s representative present.

3. a) Cut and remove the plastic strip securing the carton box to the skid.

b) Cut open the top of the carton and remove the polystyre protection sheet.

c) Pull out the polystyre posts from the corners and then remove the carton.

4. Remove the front panel of the unit and inspect for any concealed damage. Notify carrier of your claim for the concealed damage as steted in step 2 above.

5. Check that refrigerant lines do not rub against or touch other lines or surfaces, and that the fan blade moves freely.

6. Check that the compressor fits snugly onto all its mounting pads.

7. Remove all internal support packing and masking tape.

8. Use clean damp cloth to wipe the surfaces inside the storage bin and the outside of the cabinet.

9. See data plate on the rear side of the unit and check that local main voltage corresponds with the voltage specified on it.

CAUTION. Incorrect voltage supplied to the icemaker will void your parts replacement program.

10. Remove the manufacturer’s registration card from the inside of the User Manual and fillin all parts including: Model and Serial Number taken from the data plate.

GENERAL INFORMATION AND INSTALLATION

Page 20

Check voltage on the line and the ice maker’s data plate before connecting the unit.

E. WATER SUPPLY AND DRAIN

CONNECTIONS GENERAL

When choosing the water supply for the ice cuber consideration should be given to:

a) Length of run

b) Water clarity and purity

c) Adequate water supply pressure Since water is the most important single ingredient

in producting ice you cannot emphasize too much the three items listed above. Low water pressure, below 1 bar may cause malfunction of the ice maker unit. Water containing excessive minerals will tend to produce cloudy coloured ice cubes, plus scale build-up on parts of the water system.

WATER SUPPLY Air Cooled Versions

Connect the 3/4" male fitting of the solenoid water inlet valve, using the flexible tube supplied, to the cold water supply line with regular plumbing fitting and a shut-off valve installed in an accessible position between the water supply line and the unit. If water contains a high level of impurities, it is advisable to consider the use an appropriate water filter or conditioner.

Water supply - Water cooled models

The water cooled versions of SCOTSMAN Ice Makers require two separate inlet water supplies, one for the water sprayed for making the ice cubes and the other for the water cooled condenser. Connect the 3/4" GAS male fitting of the water inlet, using the flexible tubing or a 3/8" O.D. copper pipe, to the cold water supply line with regular plumbing fitting and a shut-off valve installed in an accessible position between the water supply line and the unit.

WATER DRAIN

The recommended drain tube is a plastic or flexible tube with 18 mm (3/4") I.D. which runs to an open trapped and vented drain.

WATER DRAIN - WATER COOLED MODELS

Connect the 3/4" male fitting of the condenser water drain, utilizing a second flexible hose, to the open trapped and vented drain.

NOTE.

The water supply and the water drain must be installed to conform with the local code. In some case a licensed plumber and/ or a plumbing permit is required.

WATER DRAIN - EC version

The water can be pumped out up to 1.5 m rise or

to 30 m on horizontal length.

F. FINAL CHECK LIST

1. Is the unit in a room where ambient temperatures are within a minimum of 10°C (50°F) even in winter months?

2. Is there at least a 15 cm (6") clearance around the unit for proper air circulation?

3. Is the unit level? (IMPORTANT)

4. Have all the electrical and plumbing connections been made, and is the water supply shut-off valve open?

5. Has the voltage been tested and checked against the data plate rating?

6. Has the water supply pressure been checked to ensure a water pressure of at least 1 bar (14 psi).

7. Check all refrigerant lines and conduit lines to guard against vibrations and possible failure.

8. Have the bolts holding the compressor down been checked to ensure that the compressor is snugly fitted onto the mounting pads?

9. Have the bin liner and cabinet been wiped clean?

POWER

WATER INLET

WATER DRAIN

HAND DISCONNECT

SWITCH

WATER

FILTER

WATER

VALVE

POWER

WATER INLET

WATER DRAIN

HAND DISCONNECT

SWITCH

WATER

FILTER

WATER

VALVE

Page 21

G. INSTALLATION PRACTICE

1. Hand shut-off valve

2. Water filter

3. Water supply line (flexible hose)

4. 3/4" male fitting

5. Vented drain

6. Open trapped vented drain

7. Drain fitting

8. Main switch

9. Power line

WARNING. This icemaker is not designed for outdoor installation and will not function in ambient temperatures below 10°C (50°F) or above 40°C (100°F). This icemaker will malfunction with water temperatures below 5°C (40°F) or above 35°C (90°F).

10. Has the owner/user been given the User Manual and been instructed on the importance of periodic maintenance checks?

11. Has the Manufacturer’s registration card been filled in properly? Check for correct model

and serial number against the serial plate and mail the registration card to the factory.

12. Has the owner been given the name and the phone number of the authorized SCOTSMAN Service Agency serving him?

Page 22

START UP

After having correctly installed the ice maker and completed the plumbing and electrical connections, perform the following “Start-up” procedure.

A. Turn the unit ON by the main switch. Unit will start up in charging cycle mode.

NOTE. Every time the unit returns under power, after having been switched off, the water inlet valve, the hot gas valve and the water drain valve get energized for a period of 5 minutes, thus to admit new water to the machine sump reservoir to fill it up and, eventually, to wash-off any dirt that can have deposited in it during the unit off period (Fig.1).

B. During the water filling operation, check to see that the incoming water dribbles, through the evaporator platen dribbler holes, down into the sump reservoir to fill it up and also that the

OPERATING INSTRUCTIONS

incoming surplus of water flows out through the overflow pipe into the drain line.

During the water filling phase the components energized are:

THE WATER INLET SOLENOID VALVE THE HOT GAS SOLENOID VALVE THE WATER DRAIN SOLENOID VALVE (ONLY

AC/EC 127-177).

NOTE. If in the 5 minutes lenght of the water

filling phase the machine sump reservoir does not get filled with water up to the rim of the overflow pipe, it is advisable to check:

1.The water pressure of the water supply line that must be at least 1 bar (14 psig) Minimum (Max 5 bar-70 psig).

2.The filtering device installed in the water line that may reduce the water pressure below the Minimum value of 1 bar (14 psig).

3. Any clogging situation in the water circuit like the inlet water strainer and/or the flow control.

FIG. 1

Rx Tx

WATER IN VALVE

HOT GAS VALVE

COMPRESSOR

FAN MOTOR

WATER PUMP

- EVAPORATOR

- CONDENSER

TEMPERATURE SENSORSBIN

TRANSF.

D ATA

PROCESSOR

ELECTR.

TIMER

DIP SWITCH

ELECTRONIC CARD

RELAYS

RELAY

TRIAC

WATER DRAIN VALVE

Page 23

In case of air condenser filter clogged such to prevent the proper flow of the cooling air or, in case the fan motor is out of operation or shortage of water in the water cooled condenser, the condenser temperature rises and when it reaches 70°C (160°F) - for air cooled version - or 60°C (140°F) - for water cooled version - the condenser temperature sensor shuts-off the ice maker with the consequent light-up of the RED WARNING LED (Fig.3) as well as the Red Alarm Light (ON Steady).

After having diagnosed the reason of the rise of temperature and removed its cause, it is necessary to Switch OFF (wait few seconds) and Switch ON the unit, thus to put the machine in condition to initiate a new freezing cycle.

The machine restarts with the usual 5 minutes water filling phase in order to provide enough water into the sump tank.

C. At completion of the water filling phase (5 minutes) the unit passes automatically into the freezing cycle with the start up of:

COMPRESSOR WATER PUMP FAN MOTOR (in air cooled version) controlled by

the condensing temperature sensor located within the condenser fins (Fig.2).

OPERATIONAL CHECKS D. Install, if required, the refrigerant service

gauges on both the high side and low side Scraeder valves to check the compressor head and suction pressures.

NOTE. On air cooled models, the condenser temperature sensor, which is located within the condenser fins, keep the head (condensing) pressure between values as per discharge pressure details at pag. 31.

FIG. 2

Rx Tx

WATER IN VALVE

HOT GAS VALVE

COMPRESSOR

FAN MOTOR

WATER PUMP

- EVAPORATOR

- CONDENSER

TEMPERATURE SENSORSBIN

TRANSF.

D ATA

PROCESSOR

ELECTR.

TIMER

DIP SWITCH

ELECTRONIC CARD

RELAYS

RELAY

TRIAC

WATER DRAIN VALVE

Page 24

E. Check to see through the ice discharge opening that the spray system is correctly seated and that the water jets uniformely reach the

interior of the inverted mold cups; also make sure that the plastic curtain is hanging freely and there is not excessive water spilling through it.

FIG. 3

FIG. 4

Rx Tx

WATER IN VALVE

HOT GAS VALVE

COMPRESSOR

FAN MOTOR

WATER PUMP

- EVAPORATOR

- CONDENSER

TEMPERATURE SENSORSBIN

TRANSF.

D ATA

PROCESSOR

ELECTR.

TIMER

DIP SWITCH

ELECTRONIC CARD

RELAYS

RELAY

TRIAC

WATER DRAIN VALVE

xTxR

EVLAVNIRETAW

EVLAVSAGTOH

ROSSERPMOC

ROTOMNAF

PMUPRETAW

ROTAROPAVE-

RESNEDNOC-

TEMPERATURE SENSORSBIN

.FSNART

DATA

PROCESSOR

.RTCELE

REMIT

PID

HCTIWS

DRACCINORTCELE

SYALER

YALER

CAIRT

EVLAVNIARDRETAW

Page 25

F. The ice making process takes place thereby, with the water sprayed into the molds that gets gradually refrigerated by the heat exchange with the refrigerant flowing into the evaporator serpentine. During the freezing process, the evaporator temperature falls to 0°C (Red Led blinking as per Fig. 4) and then to -15°C (Red Led ON steady as per Fig. 4a). When it reaches

-15°C the evaporator temperature sensor supplies a low voltage power signal to the electronic control device (P.C.BOARD) in order to activate an electronic timer. This one takes over the control of the freezing cycle up to the complete formation of the ice cubes.

NOTE. The lenght of the entire freezing cycle is governed by the evaporator temperature sensor which has its probe placed in contact with the evaporator serpentine (Non adjustable) in combination with the electronic timer (Adjustable) incorporated in the P.C.BOARD. The timer adjustment is factory set in consideration of the ice maker type, cooling version and ice cube size (Small, Medium, Large). It is possible, however, to modify the timed lenght of the freezing cycle, by changing the DIP SWITCH keys setting. In Table B of PRINCIPLE OF OPERATION are shown the various time extensions of the freezing cycle second phase, in relation with the different DIP SWITCH keys setting.

G. After about 17÷20 minutes from the begin- ning of the freezing cycle, in an hypothetic ambient temperature of 21°C, the defrost cycle takes place with the hot gas, the water inlet

and the water drain valves simoultaneously activated (Fig. 5). The electrical components in operation on models are:

COMPRESSOR WATER INLET VALVE HOT GAS VALVE WATER DRAIN VALVE only AC/EC 127-177 WATER PUMP

on the first 15 seconds on models only AC/EC 127-177.

NOTE. The lenght of the defrost cycle is automatically determinated by the microprocessor of the P.C. BOARD in relation of the time necessary for the unit to reduce the evaporator temperature from 0°C (32°F) small Red LED blinking to -15°C (5°F) small Red LED ON steady - TIME T2. I

t is possible to extend the length of the defrost

cycle by changing the setting of DIP SWITCH 7 and 8 as shown on table at page 37.

H. Check, during the defrost cycle, that the incoming water flows correctly into the sump reservoir in order to refill it and that the surplus overflows through the overflow drain tube.

I. Check the texture of ice cubes just released. They have to be in the right shape with a small depression of about 5-6 mm in their crown. If not, wait for the completion of the second cycle before performing any adjustment.

FIG. 4a

Rx Tx

WATER IN VALVE

HOT GAS VALVE

COMPRESSOR

FAN MOTOR

WATER PUMP

- EVAPORATOR

- CONDENSER

TEMPERATURE SENSORSBIN

TRANSF.

D ATA

PROCESSOR

ELECTR.

TIMER

DIP SWITCH

ELECTRONIC CARD

RELAYS

RELAY

TRIAC

WATER DRAIN VALVE

Page 26

• Optical level sensor (IR); place some ice cubes between IR optical sensing eyes. The Bin Full YELLOW LED starts blinking (Fig. 6), and when defrost cycle is over, the unit stops with the simultaneous glowing of the same LED to monitor the BIN FULL situation (Fig. 6a).

• Whenever necessary, pcb can be "calibrated" to assure the best comunication between the same and ice level device just by turn the Main switch OFF an ON again.

Take the hand out from the ice level control sensors to allow the resumption of the light beam. After approximately 6 seconds the ice maker resume its operation with the immediate glowing of the FIRST YELLOW LED indicating UNIT IN

OPERATION and the extinguishing of the “BIN FULL” YELLOW LED.

NOTE. The ICE LEVEL CONTROL (INFRARED SYSTEM) is independent of

the temperature however, the reliability of its detection can be affected by external light radiations or by any sort of dirt and scale sediment which may deposit directly on the light source and on the receiver.To prevent any possible ice maker malfunction, due to negative affection of the light detector, it is advisable to locate the unit where it is not reached by any direct light beam or light radiation, also it is recommended to keep the bin door constantly closed and to follow the instructions for the periodical cleaning of the light sensor elements as detailed in the MAINTENANCE AND CLEANING PROCEDURES. This ice maker is equipped by an I/R selfcalibration PC Board every time ice maker is turned OFF and ON by the main switch.

FIG. 5

Rx Tx

WATER IN VALVE

HOT GAS VALVE

COMPRESSOR

FAN MOTOR

WATER PUMP

- EVAPORATOR

- CONDENSER

TEMPERATURE SENSORSBIN

TRANSF.

D ATA

PROCESSOR

ELECTR.

TIMER

DIP SWITCH

ELECTRONIC CARD

RELAYS

RELAY

TRIAC

WATER DRAIN VALVE

If the ice cubes are shallow and cloudy, it is possible that the ice maker runs short of water during the freezing cycle second phase or, the quality of the supplied water requires the use of an appropriate water filter or conditioner. Only EC version as soon as the water into the Sealed Water Reservoir reaches the maximum level, the two metal pins close the electrical contact through the water, transmitting a low voltage current to the PC Board.

The PC Board activates the Water Drain Pump for 8 seconds pumping out most of the water contained into the Sealed Water Reservoir.

J. Upon the model, these icemakers range shall operate either by IR control device which operates by sensing eyes or Thermal sensor. Thermal sensor can detecting both the low temperature of the ice also the mass of the ice near its sensing bulb.

For testing devices:

• Storage bin thermal sensor; place some ice cubes in contact with the bulb, icemaker turn OFF at the end of harvest cycle. Remove ice from the bulb, ice maker restart from new freezing cycle.

Page 27

FIG. 6

Rx Tx

WATER IN VALVE

HOT GAS VALVE

COMPRESSOR

FAN MOTOR

WATER PUMP

- EVAPORATOR

- CONDENSER

TEMPERATURE SENSORSBIN

TRANSF.

D ATA

PROCESSOR

ELECTR.

TIMER

DIP SWITCH

ELECTRONIC CARD

RELAYS

RELAY

TRIAC

WATER DRAIN VALVE

FIG. 6a

Rx Tx

WATER IN VALVE

HOT GAS VALVE

COMPRESSOR

FAN MOTOR

WATER PUMP

- EVAPORATOR

- CONDENSER

TEMPERATURE SENSORSBIN

TRANSF.

D ATA

PROCESSOR

ELECTR.

TIMER

DIP SWITCH

ELECTRONIC CARD

RELAYS

RELAY

TRIAC

WATER DRAIN VALVE

K. Remove, if fitted, the refrigerant service gauges and re-fit the unit service panels previously removed.

L. Instruct the owner/user on the general operation of the ice machine and about the cleaning and care it requires.

Page 28

PRINCIPLE OF OPERATION

How it works

In the SCOTSMAN cube ice makers the water used to make the ice is kept constantly in circulation by an electric water pump which primes it to the spray system nozzles from where it is diverted into the inverted mold cups of the evaporator. A small quantity of the sprayed water freezes into ice; the rest of it cascades by gravity into the sump assembly below for recirculation.

FREEZING CYCLE (Fig. A and B)

The hot gas refrigerant discharged out from the compressor reaches the condenser where, being cooled down, condenses into liquid. Flowing into the liquid line it passes through the drier filter, then it goes all the way through the capillary tube where, due to the heat exchanging action, it looses some of its heat content so that its pressure and temperature are lowered as well. Next the refrigerant enters into the evaporator serpentine (which has a larger I.D. then the capillary) and starts to boil off; this reaction is emphasized by the heat transferred by the sprayed water. The refrigerant then increases in volume and changes entirely into vapor. The vapor refrigerant then passes through the suction accumulator (used to prevent that any small amount of liquid refrigerant may reach the compressor) and through the suction line. In both the accumulator and the suction line it exchanges heat with the refrigerant flowing into the capillary tube (warmer), before to be sucked in the compressor and to be recirculated as hot compressed refrigerant gas.

The freezing cycle is controlled by the evaporator temperature sensor (which has its probe in contact with the evaporator serpentine) that determines the length of its first portion of the cycle. When the temperature of the evaporator serpentine drops to a pre-set value (small Red LED ON steady) the evaporator sensor probe changes its electrical resistance allowing a low voltage current (15 volts) to flow to the P.C. BOARD which in turn activates an electronic timer. The timer, which is built-in the P.C. BOARD, takes over from the evaporator temperature sensor, the control of the freezing cycle up to its completion.

NOTE. The change of the electric potential of the evaporator sensor with the consequent activation of the timer (Time mode) is signalled by the glowing-up of the RED LED located in the front of the P.C. BOARD.

ATTENTION. In case, after 15 minutes from the beginning of the freezing cycle, the temperature of the evaporator sensor probe is higher then 0° C (32°F) - small Red LED still OFF - (shortage of refrigerant, inoperative hot gas valve, etc.) the P.C. BOARD switch OFF immediately the unit with the simultaneous blinking of the WARNING RED LED.

The length of this timed portion of the freezing cycle is pre-fixed and related to the setting of the first four DIP SWITCH keys. The DIP SWITCH keys setting is made in consideration of the type of condenser used and size of ice cubes.

AC-EC M 47 A AC-EC M 47 W AC-EC M 57 A AC-EC M 57 W AC-EC M 87 A AC-EC M 87 W AC-EC M 107 A AC-EC M 107 W AC-EC M 127 A AC-EC M 127 W AC-EC M 177 A AC-EC M 177 W

OFF

TAB. A

1234

56 7 8 9 10

OFF

DIP SWITCH FACTORY SETTING COMBINATIONS (PER MODEL AND VERSION)

DIP SWITCH

FREEZING CYCLE

DEFROST CYCLE

15/30"

AIR/WATER

DEFROST CYCLE

ADD. TIME

Page 29

FIG. B

FIG. A

FIG. D

FIG. C

Page 30

the ice maker model with the growing of the ice thickness with the cubes fully formed in the cup molds. The total length of the freezing cycle ranges from 20 to 25 minutes.

DEFROST OR HARVEST CYCLE (Fig.C and D)

As the electronic timer has carried the system throughout the second phase of freezing cycle, the defrost cycle starts.

ATTENTION. In case the unit is able to reach 0°C (32°F) evaporating temperature within 15 minutes, but after 45 minutes from the beginning of the freezing cycle it has not yet reached the evaporator temperature of -15°C (5°F) the machine goes straight into the defrost cycle omitting the timed portion of the freezing cycle relied to the setting of the first four DIP SWITCHES.

NOTE. The length of the defrost cycle is

related to the length of the second phase of freezing cycle T2. (Time to drop the evaporating temperature from 0°C (32°F) small Red LED blinking - to -15°C (5°F) small Red LED ON steady. I

t is possible to extend the length of the defrost

cycle by changing the setting of DIP SWITCH 7 and 8 as shown on table at page 34.

The electrical components in operation during this phase are:

COMPRESSOR WATER INLET VALVE HOT GAS VALVE WATER DRAIN VALVE (ONLY AC/EC 127-177)

and the

WATER PUMP

on the first 15 seconds. The incoming water, passing through the water

inlet valve and the flow control, runs over the evaporator platen and then flows by gravity through the dribbler holes down into the sump/ reservoir. (Fig. D ) The water filling the sump/reservoir forces part of the surplus water from the previous freezing cycle to go out to the waste through the overflow pipe. This overflow limits the level of the sump water which will be used to produce the next batch of ice cubes. Meanwhile, the refrigerant as hot gas, discharged from the compressor, flows through the hot gas valve directly into the evaporator serpentine by-passing the condenser. The hot gas circulating into the serpentine of the evaporator warms up the copper molds causing the defrost of the ice cubes. The ice cubes, released from the cups, drop by gravity onto a slanted cube chute, then through a curtained opening they fall into the storage bin. At the end of the defrost cycle, the hot gas valve, the water inlet valve and the water drain valve close and the machine starts again a new freezing cycle.

In Table B are indicated the various lengths of the timed portion of freezing cycle in relation to the different combinations of the DIP SWITCH KEYS. In Table A are illustrated the DIP SWITCH keys combinations for the different models and versions as they are set in the factory. The electrical components in operation during the freezing cycle are:

COMPRESSOR FAN MOTOR (in air cooled version) WATER PUMP

and during the second phase of freezing cycle (Time mode) they are joined by the

ELECTRONIC TIMER

The refrigerant head pressure, at avarage 21 °C amb. temp., in the course of the freezing cycle, ranges between 15,5 - 10 bar according to the model in the air cooled version, being controlled by the temperature sensor probe located within the condenser fins. On the air cooled version, the condenser temperature sensor, when senses a rising of the condenser temperature beyond the pre-fixed limit, changes its electrical resistance and transmits a low voltage power flow to the Micro Processor of P.C. BOARD which in turn energizes, through a TRIAC, the FAN MOTOR. When the opposite situation occures, i.e. the condenser temperature gets below the pre-fixed limit, the temperature sensor changes again its electrical resistance reducing therefore the current flow to the P.C. BOARD to cause the fan motor temporary cut-off.

NOTE. In case the condenser temperature probe senses that the condenser temperature has rised to 70°C (160°F) - on air cooled versions - or 60°C (140°F) - on water cooled versions - for one of the following reasons:

CLOGGED CONDENSER (Air cooled version)

INSUFFICIENT FLOW OF COOLING WATER (Water cooled version)

FAN MOTOR OUT OF OPERATION (Air

cooled version)

AMBIENT TEMPERATURE HIGHER THEN 40°C (100°F)

it causes the total and immediate SHUT-OFF

of the machine in order to prevent the unit from operating in abnormal and dangerous conditions. When the ice maker stops on account of this protective device, there is a simultaneous glowing of the RED LED and RED LIGHT (STEADY), warning the user of the Hi Temperature situation. After having eliminated the source of the condenser hitemperature, to restart the machine it is necessary to switch OFF (wait few seconds) and switch ON again the unit. The ice machine resumes its normal operation by

going through

the 5 minutes water filling phase.

At the start of the freezing cycle the refrigerant suction or lo-pressure starts from 3,8 - 7,7 bar and it declines gradually to 1,8 - 0,6 according to

Page 31

HARVEST (Drain portion - first 15 sec.)

Electrical components (Loads) ON OFF

Compressor............................................

•

Fan Motor (Air cooled only)and TRIAC .........

•

Hot Gas Valve ........................................ •

Water Inlet Valve....................................•

Water Drain valve

(only AC/EC 127-177)

•

P.C.Board Relay 1 & 2 Coil....................•

P.C.Board Relay 3 Coil

...............................

•

Water Pump ...........................................•

P.C.B. Timer...........................................•

Electronic Controls & Sensors ON OFF

Evaporator Sensor .................................

•

Condenser Sensor ................................. •

Ice Level Control ....................................•

HARVEST (Water filling portion)

Electrical components (Loads) ON OFF

Compressor............................................

•

Fan Motor (Air cooled only)and TRIAC .........

•

Hot Gas Valve ........................................ •

Water Inlet Valve....................................•

Water Drain valve

(only AC/EC 127-177)

•

P.C.Board Relay 1 & 2 Coil....................•

P.C.Board Relay 3 Coil

...............................

•

Water Pump ........................................... •

P.C. Board Timer ...................................•

Electronic Controls & Sensors ON OFF

Evaporator Sensor .................................

•

Condenser Sensor ................................. •

Ice Level Control ....................................•

OPERATING CHARACTERISTICS

OPERATING PRESSURE (bar) at 21°C amb. Temp.

AC 47 AC 57 AC 87 AC 107 AC 127 AC 177

SUCTION PRESSURE beg./end freezing

2,8/0,8 3,5/1,1 2,8/1,8 2,8/0,6 2,7/1,1 3,2/0,7

DISCHARGE PRESSURE

12/10,5 12,5/11 12/10,5 13/10 12/10,5

15,5/10,5

REFRIGERANT METERING DEVICE:

capillary tube

REFRIGERANT CHARGE (R 290) grs:

Air cooled Water cooled

AC/EC 47 100 AC/EC 57 100 AC/EC 87 100 AC/EC 107 120 AC/EC 127 130 AC/EC 177 170

AC 177 110 gr (3.88 oz.)

OPERATION - CONTROL SEQUENCE

At the start of freezing cycle the evaporator temperature sensor controls the length of the first part of the freezing cycle. As it reaches a predetermined temperature it supplies a low voltage current to the P.C. BOARD in order to activate the electronic timer which takes over the control of the freezing cycle for a pre-fixed time according to the DIP SWITCH keys setting (see Tab. B).

NOTE. The evaporator temperature sensor, factory pre-set, is the same for all the models and is not adjustable in the field.

Once completed the timed portion of the freezing cycle the system goes automatically into the defrost cycle which has also a pre-fixed length. At completion of the defrost cycle the P.C. BOARD command the unit to start again a new freezing cycle.

OPERATION - ELECTRICAL SEQUENCE

The following charts illustrate which switches and which components are ON or OFF during a particular phase of the icemaking cycle. Refer to the wiring diagram for a reference.

BEGINNING FREEZE

Electrical components (Loads) ON OFF

Compressor ...........................................

•

Fan Motor (Air cooled only) and TRIAC ........

•

Hot Gas Valve ........................................ •

Water Inlet Valve.................................... •

Water Drain Valve

(only AC/EC 127-177)

•

P.C.Board Relay 1 Coil .......................... •

P.C.Board Relay 2 & 3 Coil....................•

Water Pump ...........................................•

P.C.B. Timer........................................... •

Elctronic Controls & Sensors ON OFF

Evaporator Sensor .................................

•

Condenser Sensor .................................•

Ice Level Control ....................................•

TIMED FREEZE

Electrical components (Loads) ON OFF

Compressor............................................

•

Fan Motor (Air cooled only) and TRIAC ........

••

Hot Gas Valve ........................................ •

Water Inlet Valve.................................... •

Water Drain Valve

(only AC/EC 127-177)

•

P.C.Board Relay 1 Coil .......................... •

P.C.Board Relay 2 & 3 Coil....................•

Water Pump ...........................................•

P.C.B. Timer...........................................•

Electronic Controls & Sensors ON OFF

Evaporator Sensor .................................

•

Condenser Sensor .................................••

Ice Level Control ....................................•

Page 32

COMPONENTS

The components of the Pump Out Water Drain System are

• Sealed water tank

• PC Board & Sensor

• Sealed Water Pump

• Check Valve

OPERATION

All water coming from the overflow, and from the melted ice is collected inside the Sealed Water Reservoir.

As soon as the water into the Sealed Water Reservoir reaches the maximum level, the two metal pins close the electrical contact through the water, transmitting a low voltage current to the PC Board.

The PC Board activates the Water Drain Pump for 8 seconds pumping out most of the water contained into the Sealed Water Reservoir.

PWD SYSTEM (EC version only)

The water can be pumped out up to 1.5 m rise or

to 30 m on horizontal length.

POWER

WATER INLET

WATER DRAIN

HAND DISCONNECT

SWITCH

WATER

FILTER

WATER

VALVE

POWER

WATER INLET

WATER DRAIN

HAND DISCONNECT

SWITCH

WATER

FILTER

WATER

VALVE

A Check Valve, located on the water drain hose, prevents the coming back of the discharged water.

Page 33

SCHEMATIC SYSTEM

Storage bin

Overflow drain tube

Storage bin drain tube

Water tank inlet fitting

Sealed water tank

Water pump

Check valve

Vented tube

Water

level

sensors

Drain out

Drain fitting

Page 34

COMPONENTS DESCRIPTION

A. EVAPORATOR TEMPERATURE

SENSOR

The evaporator temperature sensor probe, located in contact with the evaporator serpentine, detects the dropping of the evaporator temperature during the freezing cycle and signals it by supplying a current flow to the micro processor of P.C. BOARD. According to the current received is energized the small Red LED of the PC Board (blink or steady). When steady, the micro processor supplies power to the electronic timer built into the P.C. BOARD so that it takes control of the last portion of freezing cycle. The length of the timed phase is pre-fixed by the setting of the keys 1, 2, 3 and 4 of the DIP SWITCH.

NOTE. Whenever, after 15 minutes from the beginning of the freezing cycle, the evaporating temperature have not yet reached the value of 0°C (32°F) - small Red LED OFF

- the P.C.Board switches OFF the machine with the BLINKING of WARNING RED LED.

B. CONDENSER TEMPERATURE

SENSOR

The condenser temperature sensor probe, located within the condenser fins (air cooled version) or in contact with the tube coil (water cooled version) detects the condenser temperature variations and signals them by supplying current, at low voltage, to the P.C. BOARD. In the air cooled versions, in relation to the different current received, the micro processor of the P.C. BOARD supplies, through a TRIAC, the power at high voltage to the fan motor so to cool the condenser and to reduce its temperature. In case the condenser temperature rises and reaches 70°C (160°F) - on air cooled models - or 60°C (140°F) - on water cooled models - the

current arriving to the micro processor is such to cause an immediate and total stop of the machine operation.

C. ICE LEVEL THERMAL PROBE

It operayes in detecting both the low temperature of the ice and the mass near the bin sensing bulb.

D. ICE BIN LEVEL LIGHT CONTROL

The electronic ice bin level control, located into the storage bin, has the function to stop the operation of the ice machine only at the end of the harvest cycle when the light beam between the light source and the sensor is interrupted by the ice cubes stored into the bin. When the light beam is interrupted the Bin Full YELLOW LED starts to blink; the ice machine stops with the glowing-up of the Bin Full YELLOW LED to monitor the situation of ice bin full at the end of the harvest cycle. Six seconds after the scoop out of the ice (with the resumption of the light beam between the two infrared sensor of ice level control) the ice machine restarts again with the extinguishing of the YELLOW LED.

E. P.C. BOARD

(Data processor)

The P.C. BOARD, fitted in its plastic box located in the front of the unit, consists of two separated printed circuits one at high and the other at low voltage integrated with fuse on power out (6.3 A), of four aligned LEDS monitoring the operation of the machine, of one extra monitoring RED LED (blink 0°C - steady - 15°C), of one DIP SWITCH with ten keys, of one push button, of input terminals for the leads of the sensor probes and input and output terminals for the leads of the ice maker electrical wires.

Page 35

The P.C. BOARD is the brain of the system and it elaborates, through its micro processor, the signals received from the three sensors in order

6-12

MONTHS

EC SERIES

0 OR 60 MINUTES

DELAY

TEST

ON STEADY

BLINKING

0-12

MONTHS

to control the operation of the different electrical components of the ice maker (compressor, water pump, solenoid valves, etc.).

At restart, from any tripping OFF at Bin Full, the new PC Board assures 45 seconds water filling phase so to refill the water sump up to the maximum level. In case of malfunction of the Optical Ice Level Control, thenew PC Board switch ON alternativelt the Yellow and Red Led continuously.

On the PC Board there are four jumpers to select:

• 0 or 12 months remind time for the water system cleaning

• Operation of the Purge Out Water Pump (Jump IN on EC series)

• "no delay" or 60 minutes delay time at first start up

• TEST

In case the TEST contacts are closed with the Jumper, at the Start Up of the machine the PC Board energizes all the electrical components for maximum 3 minutes time.

At the end of the 3 minutes the PC Board switch OFF the entire machine with the blinking of all the LED's as shown on the bottom drawing.

Page 36

F. PUSH BUTTON OPERATION

DURING WATER FILLING PHASE

• Push for more then 2” but less then 5” the

machine enters in Cleaning Mode

• Push for more then 5” the machine by-pass

the Water Filling Phase

DURING FREEZING/HARVEST CYCLE

• Push for more then 5” during the Freezing

cycle the machine goes immediately into Harvest

• Push for more then 5” during the Harvest cycle

the machine enters immediately in the Freezing cycle

The length of Harvest is equal to:

•35” if Push Button is activated before 15°C evaporating temperature LED activation

•As per Harvest cycle chart, if Push Button is activated after -15°C evaporating temperature LED activation (Red LED inside PC Board ON steady)

• Push more then 20” to restore remind cleaning

timer.

G. LED MEANING GREEN LED ON

Unit under power

YELLOW BIN FULL LED ON

Unit shut-OFF at storage bin full

YELLOW BIN FULL LED BLINKING

Infrared beam break out

RED ALARM LED ON

Too hi condensing temperature

RED ALARM LED BLINKING

Too hi evaporating temperature

YELLOW FREEZING CYCLE ON

Unit in freezing cycle mode

YELLOW FREEZING LED AND RED ALARM LED ON

Condenser sensor out of order

YELLOW FREEZING LED AND RED ALARM LED BLINKING

Evaporator sensor out of order

FREEZING CYCLE

BIN FULL

POWER

TOO HI EVAP TEMP

TOO HI COND TEMP

PUSH BUTTON

LED STATUS

REASON WHY

ON STEADY UNIT UNDER POWER

ON STEADY FREEZING CYCLE

BLINKING

60 MINUTES DELA Y AT START UP JUMPER J3 OUT

ON STEADY

TOO HI DISCHARGE PRESSURE/TEMP

BLINKING

TOO HI EVAP. TEMP. (> 0C°) AFTER 15’ FROM START UP

ON STEADY UNIT OFF AT BIN FULL

BLINKING

SLOW

I/R BEAM CUTTED

I/R ON AFTER TRIP OFF AT BIN FULL

BLINKING

FAST

ON STEADY I/R CALIBRATION DONE

BLINKING

UNIT IN CLEANING MODE OR TRIPPING OFF AFTER TEST - JUMPER TEST IN

ON STEADY

CONDENSER SENSOR OUT OF ORDER

BLINKING

EVAPORATOR SENSOR OUT OF ORDER

BLINKING

ALTERNATIVELY

I/R SENSOR OUT OF ORDER

PUSH

PUSH > 5” DURING WATER FILLING TO

MOVE THE UNIT INTO FREEZING

PUSH > 5” DURING FREEZING

TO MOVE THE UNIT INTO DEFROST

PUSH > 5” DURING DEFROST

TO MOVE THE UNIT INTO FREEZING

PUSH 2” > 5” DURING WATER FILLING

TO MOVE THE UNIT INTO CLEANING

PUSH DURING THE 60 MIN START UP

DELAY TIME TO BY-PASS IT

H. DIP SWITCH

The P.C.BOARD which controls the entire operation of the ice maker, has a DIP SWITCH with ten switching keys which allow to set up the micro processor program in order to extend

or to shorten the length of freezing cycle in relation to the different model and versions of ice machines.

The DIP SWITCH first four keys setting

determines the length of the 2nd phase of freezing cycle (controlled by the electronic timer) as detailed in the table B.

The DIP SWITCH keys 5 & 6 setting determines the length of the defrost cycle according to the

Page 37

LENGTH OF TIMED PORTION OF FREEZING CYCLE ACCORDING TO THE

DIP SWITCH SETTING COMBINATIONS

TAB. B

size of the cubes (Large or Medium) as per the following setting: ON ON : PROGRAM A ON OFF : PROGRAM B OFF OFF : PROGRAM C OFF ON : PROGRAM D

LENGTH OF HARVEST CYCLE

ACCORDING TO THE TIME TO DROP THE

EVAP. TEMPERATURE FROM 0°C TO -15°C

LENGTH PROGRAMS

HARVEST

CYCLE

ABC D

180” Up to 6’30” *** Up to 9’30” xxxx 165” 6’30”-7’ Up to 3’ 9’30”-10’ xxxx 150” 7’-8’ 3’-3’15’ 10’-11’ xxxx 135” 8’-9’ 3’15”-3’30” 11’-12’ xxxx 120” 9’-10’30” 3’30”-4’30” 12’-13’30” < 3' 105” 10’30”-12’ 4’30”-6’ 13’30”-15’ 3' - 4'

90” >12’ >6’ >15’ > 4'

The DIP SWITCH N° 7 and 8 allow the extention of the length of the harvest/defrost cycle according to their combination as per following chart:

DIP SWITCH ADDITIONAL DEFROST TIME

ON ON 0

OFF ON 30"

ON OFF 60"

With both DIP SWITCH 7 & 8 in OFF position, Water Pump is OFF during the Harvest Cycle with no additional time.

The 9th key is used to supply power to the water pump for the first 15 seconds of the defrost cycle

- position OFF - or for the first 30 seconds -

position ON. The 10th key is used to modify the CUT-OUT

condensing temperature from 70°C (160°F) for the air cooled versions - ON position - to 60°C (140°F) - OFF position - for the water cooled versions.

I. CONDENSER AIR FILTER

(Air cooled version)

Located in front of the air cooled condenser can be removed by withdrawing it through the opening of the front panel for cleaning or replacing. A lower plastic guide, installed inside the unit, is used for the correct sliding and location of the air filter.

L. WATER SPRAY SYSTEM

Through its nozzles, the water pumped, is sprayed in each individual cup to be frozen into ice. It consists of one spray tube wheve are located several spray nozzles.

M. WATER PUMP

The water pump operates continually throughout the freezing cycle and on the first 15 or 30 seconds of the defrost cycle so to such the remaining water from the sump tank (reach in mineral salts) and drain it out. During the freezing cycle the pump primes the water from the sump to the spray system and through the spray nozzles sprays it into the inverted cup molds to be frozen into crystal clear ice cubes. It is recommended that the pump motor bearings be checked at least every six months.

N. WATER INLET SOLENOID VALVE -

3/4 MALE FITTING

The water inlet solenoid valve is activated by the micro processor of the P.C. BOARD during the first 5 minutes of water filling phase as well as during the defrost cycle. When energized it allows a metered amount of incoming water to flow over the evaporator cavity to assist the hot gas in defrosting the ice cubes. The water running over the evaporator cavity drops by gravity, through the dribbler holes of the platen, into the sump reservoir where it will be sucked by the water pump and primed to the spray system.

Page 38

O. WATER INLET SOLENOID VALVE -

3/4 MALE FITTING (AC/EC 47-57-87-107 only)

A second water inlet solenoid valve is used on water cooled version. An automatic hi pressure control activates the coil of the water inlet solenoid valve so to supply a metered amount of water to the condenser and drop down its temperature and pressure.

P. HOT GAS SOLENOID VALVE

The hot gas solenoid valve consists basically in two parts: the valve body and the valve coil. Located on the hot gas line, this valve is energized through the micro processor of P.C. BOARD during the defrost cycle as well as during the water filling phase. During the defrost cycle the hot gas valve coil is activated so to attract the hot gas valve piston in order to give way to the hot gas discharged from compressor to flow directly into the evaporator serpentine to defrost the formed ice cubes.

Q. FAN MOTOR (Air cooled version)

The fan motor is controlled through the P.C. BOARD and the TRIAC by the condenser temperature sensor. Normally it operates only during the freezing cycle to draw cooling air through the condenser fins. In the second part of the freezing cycle, the fan motor can run at intermittance as the condenser pressure must be kept between two corresponding head pressure values.

R. COMPRESSOR

The hermetic compressor is the heart of the refrigerant system and it is used to circulate and retrieve the refrigerant throughout the entire system. It compresses the low pressure refrigerant vapor causing its temperature to rise

and become high pressure hot vapor which is then released through the discharge valve.

S. HI PRESSURE CONTROL

(AC/EC 47-57-87-107 only)

Used only on the water cooled versions it operates to keep between 9.5 and 10.5 bars (135 ÷ 150 psig) the hi-side or discharge pressure of the refrigerant system by energizing the coil of the water inlet solenoid valve that control the cooling water flow to the condenser.

T. WATER REGULATING VALVE

(AC/EC 127-177 only)

This valve controls the head pressure in the refrigerant system by regulating the flow of water going to the condenser. As pressure increases, the water regulating valve opens to increase the flow of cooling water.

U. WATER DRAIN SOLENOID VALVE

(AC/EC 127-177 only)

The water drain solenoid valve, electrically connected in parallel to the water inlet and to the hot gas solenoid valves, is energized for all the length of the defrost cycle. By means of the water pump, that remains energized for 15 seconds at the beginning of the defrost cycle, it allows the drain out of all remaining water (rich of minerals deposited during the previous freezing cycle) from the sump tank. By doing so it allows to the ice maker to make every new freezing cycle with new fresh water, avoiding thereby the accumulation of sediments and scales, which soon or later will cause the partial or total clogging of the water system on the unit.

Page 39

SMALL IDENTATION

LITTLE OR NO ICE IN CENTER OF CUBES

THICK BULGE SOLID ICE

ADJUSTMENT PROCEDURES

A. ADJUSTMENT OF THE CUBE SIZE

CAUTION. Before performing actual adjustment of the cube size , check other possible causes for cube size problems, refer to the Service Diagnosis Section for problem review and analysis. Do not perform any adjustment till the icemaking system has progressed through several complete freezing and harvest cycle, to observe size and quality of ice cubes and whether or not the cube size problem exists.

I. If the cubes are shallow size (Indentation is

too deep) probably the length of the second phase of the freezing cycle is too short so, to extend such length you have to:

1. Locate the DIP SWITCH on the front of the P.C.Board.

2. Take note of the combination of the first four DIP SWITCH KEYS and check the corrisponding length of freezing cycle 2nd phase on Table B.

3. Set the same DIP SWITCH KEYS to correspond to the prior combination shown on Table B which allow an extention of two more minutes of the length of the freezing cycle.

4. Observe the ice cubes in the next two harvests and eventually repeat steps 2 and 3 above until proper ice cubes size is achieved. See figure.

II. If the cubes are oversize size (Indentation is too full) probably the length of the second phase of the freezing cycle is too long. To shorten such length you have to:

1. Locate the DIP SWITCH on the front of the P.C.Board.

2. Take note of the combination of the first four DIP SWITCH KEYS and check the corrisponding length of freezing cycle 2nd phase on Table B.

3. Set the same DIP SWITCH KEYS to correspond to the next combination shown on Table B which allow a reduction of two minutes of the length of the freezing cycle.

4. Observe the ice cubes in the next two harvests and eventually repeat steps 2 and 3 above until proper ice cubes size is achieved. See figure.

Page 40

WIRING DIAGRAM

AC-EC 47-57-87-107-177 AIR AND WATER COOLED 230/50-60/1

The unit is shown on freezing cycle

Page 41

Page 42

SERVICE DIAGNOSIS

SYMPTOM POSSIBLE CAUSE SUGGESTED CORRECTION

Unit will not run Blown power in fuse in P.C.Board Replace fuse & check for cause of (No warning LEDS glows) blown fuse

Main switch in OFF position Turn switch to ON position Inoperative P.C.Board Replace P.C.Board Loose electrical connections Check wiring

(Green LED-Power ON glows) Blown power out fuse in P.C. Board Replace fuse & check for cause of

blown fuse

(Bin full LED glows) Inoperative ice level control Clean or replace ice level control

Inoperative P.C.Board Replace P.C.Board

(Red-alarm LED-LIGHT glows) High head pressure Inoperative fan motor. Replace

Shortage of water (WC)

(Red-alarm LED blinks) High evaporating temperature Hot gas valve leak - Replace it.

after 15 mins. beginning freeze Water inlet valve leak - Replace it.

Short of refrigerant. Compressor cycles intermittently

(Freezing LED + Red-alarm LED glows)

Condenser sensor out of order Replace it and Red-alarm Light blinks twice and repeat

(Freezing LED + Red-alarm LED blinks)

Evaporator sensor out of order Replace it

Compressor cycles intermittently Low voltage Check circuit for overloading

Check voltage at the supply to the building. If low, contact the power

company Non-condensable gas in system Purge the system Compressor starting device with Check for loose wires in starting

loose wires device Mechanical problem Replace compressor

Cubes too small Freezing cycle too short Review setting of DIP SWITCH keys

Capillary tube partially restricted Blow charge, add new gas & drier,

after evacuating systemwithvacuum

pump Moisture in the system Same as above Shortage of refrigerant Check for leaks & recharge

Cloudy cubes Shortage of water See remedies for shortage of water

Dirty water supply Use water softner or water filter Accumulated impurities Use SCOTSMAN Ice Machine

cleaner

Page 43

SYMPTON POSSIBLE CAUSE SUGGESTED CORRECTION

Shortage of water Water spilling out through curtain Check or replace curtain

Water solenoid valve not opening Replace valve Water leak in sump area Locate and repair Water flow control plugged Replace water inlet valve Leak of water drain valve Replace valve

Irregular cubes size & some Some jets plugged Remove jet cover and clean cloudy

Shortage of water See shortage of water Unit not level Level as required

Cubes too large Freezing cycle too long

Review setting of DIP SWITCH keys

Decreased ice capacity Inefficient compressor Replace

Leaky water valve Repair or replace Non-condensable gas in system Purge the system Poor air circulation or excessive Relocate the unit or provide for

hot location (Red-alarm LED glows

) more ventilation

Overcharge of refrigerant

Correct the charge. Purge off slowly

Capillary tube partially restricted Blow charge, add new gas & drier,

after evacuating system with

vacuum pump Hot gas solenoid valve leaking Replace valve Short of refrigerant Charge to data plate indication

Discharge head pressure too high See incorrect discharge pressure

Poor harvest Restriction in incoming water line

Check water valve strainer and flow

control. If necessary enlarge the

flow control orifice

Water inlet valve not opening Valve coil with open winding

Replace valve

Hot gas valve orifice restricted Replace hot gas valve assy

Clogged air vented holes in mold cups

Clean out holes plugged

Discharge head pressure too low See incorrect discharge pressure

SERVICE DIAGNOSIS

Page 44

SYMPTON POSSIBLE CAUSE SUGGESTED CORRECTION

Unit won’t harvest Inoperative P.C.Board Replace P.C.Board

Hot gas valve not opening Valve coil with open winding

Replace valve

Water solenoid valve not opening Valve coil with open winding

Replace valve

Incorrect discharge pressure Inoperative condenser sensor Replace sensor

Inoperative P.C.Board Replace P.C.Board

Water regulating valve misadjusted

Adjust its setting stem

Excessive water in unit base Water tubing leaking Check. Tighten or replace

SERVICE DIAGNOSIS

Page 45

MAINTENANCE AND CLEANING INSTRUCTIONS

A. GENERAL

The periods and the procedures for maintenance and cleaning are given as guides and are not to be construed as absolute or invariable. Cleaning, especially, will vary depending upon local water and ambient conditions and the ice volume produced; and, each icemaker must be maintened individually, in accordance with its particular location requirements.

B. CLEAN - REPLACE OF AIR

CONDENSER FILTER

NOTE. The new AC series, in the air cooled

version, are standard equipped with an air condenser filter as well as a Cleaning Reminder Board to remind to the end user the need for the cleaning of the air filter or of the water system (Red Alarm Light ON Steady or Blinking rispectively with machine in operation).

1. Withdraw the air filter from the front through the opening of the front panel.

2. Blow pressurised air on the opposite direction of the condenser air flow so to remove the dust accumulated.

3. If pressurised air is not available, use tap water always in the counter flow air diretcion. Once cleaned shake it so to remove most of the accumulated water, then dry it using an hair dryer.

NOTE. In case the air filter strainer is damaged replace it with a new one.

4. Install it again by pushing it through the front panel opening.

A. ICEMAKER

The following maintenance should be scheduled at least two times per year on these icemakers.

1. Check and clean the water line strainer.

2. Check that the icemaker is levelled in side

to side and in front to rear directions.

3. Check for water leaks and tighten drain line connections.

Pour water down bin drain line to be sure that drain line is open and clear.

4. Check size, condition and texture of ice cubes. Perform adjustment of cube size control as required.

5. Check the ice level control sensor to test shut-off. Put your hand between the light source and the receiver so to cut off the light beam for at least one minutes.

This should cause the ice maker to shut off and the light up of the 2nd LED (yellow light) a the end of defrost cycle.

NOTE. Within few seconds after the removal of the hand from the Infrared sensing light the icemaker restarts in freezing cycle. The ice level control uses devices that sense light, therefore they must be kept clean enough so they can "see". Every month clean/wipe the sensing "eyes" with a clean soft cloth.

6. Check for refrigerant leaks.

CLEANING/SANITISING INSTRUCTIONS OF WATER SYSTEM

Clean-sanitise the water system, evaporator, bin and spray jets using a solution of SCOTSMAN Ice Machine Cleaner/Sanitizer.

Page 46

NOTE. Cleaning requirements vary according to the local water conditions and individual user operation. Continuous check of the clarity of ice cubes and visual inspection of the water spraying parts before and after cleaning will indicate frequency and procedure to be followed in local areas.

1. Remove the front and top panels to gain access either to the control box and to the evaporator.

2. Make sure that all ice cubes have been released from their cups, then switch OFF the machine at front master button switch.

3. Scoop out all the ice cubes stored into the bin in order to prevent them from being contaminated with the cleaning solution.

4. Remove the plastic cup located on the bottom of sump/freezing chamber to drain out all water and scale deposits.

5. Lift up and remove the curtain.

6. Lift up the entire spray platen from its bottom seat and take it out to clean it separately.

7. Using a bottle, poor fresh water into the bottom of the sump/freezing chamber to clean out most of scale deposit.

8. Install again the spray platen, the curtain as well as the bottom plastic cup.

Cleaning

9. Prepare the cleaning solution by diluting in a plastic container two liters of warm water (45°50°C) with 0,2 liters of Ice Machine Cleaner.

WARNING. The SCOTSMAN Ice Machine Cleaner contains Phosphoric and Hydroxyacetic acids. These compounds are corrosive and may cause burns if swallowed, DO NOT induce vomiting. Give large amounts of water or milk. Call Physician immediately. In case of external contact flush with water. KEEP OUT OF THE REACH OF CHILDREN.

10. Remove the evaporator cover then slowly pour onto the evaporator platen the cleaning solution. With the help of a brush dissolve the most resistant and remote scale deposits in the platen.

11. Switch ON again the machine at front master button switch then push the PC BOARD

Page 47

FIG. 8

Rx Tx

WATER IN VALVE

HOT GAS VALVE

FAN MOTOR

WATER PUMP

- EVAPORATOR

- CONDENSER

TEMPERATURE SENSORSBIN

TRANSF.

D ATA

PROCESSOR

ELECTR.

TIMER

DIP SWITCH

ELECTRONIC CARD

RELAYS

RELAY

TRIAC

WATER DRAIN VALVE

COMPRESSOR

PUSH BUTTON for more then 2" and less of 5" to put the machine in cleaning mode.

NOTE.

With the system in CLEANING/ RINSING mode the water pump is the only component in operation to circulate the cleaning solution in the entire water system while the three leds of the PC Board are blinking (Fig. 8).

12. Let the unit to remain in the CLEANING mode for about 20 minutes then unplug again the machine.

NOTE.

The amount of Cleaner and the time needed for the cleaning of water system depends of the water conditions.

13. Switch OFF the ice maker at master button switch then flush out the cleaning solution from the sump reservoir by taking off the sump plastic cup. Once flushed out install again the sump plastic cup.

14. Pour onto the evaporator cavity two or three liters of clean potable water to rinse the mold cups and the platen.

15. Switch ON again the machine. The water pump is again in operation to circulate the water in order to rinse the entire water system. Do the operation as per steps 13 and 14 twice so to be sure no more traces of descaling solution remains into the sump.

REMEMBER. To prevent the accumulation of undesirable bacteria it is necessary to sanitize the interior of the storage bin with an anti-algae disinfectant solution every week.

Sanitation

NOTE. Sanitation of the water system is

recommended to be done once a month.

1. Prepare in a plastic container the sanitation solution as per manufacturer dilution using warm water (45-50 °C).

NOTE. Never mix the cleaning with the sanitising solution.

Page 48

Rx Tx

WATER IN VALVE

HOT GAS VALVE

FAN MOTOR

WATER PUMP

- EVAPORATOR

- AMBIENT

- CONDENSER

TEMPERATURE SENSORSBINCOMPRESSOR

TRANSF.

DATA

PROCESSOR

ELECTR.

TIMER

DIP SWITCH

ELECTRONIC CARD

RELAYS

RELAY

TRIAC

WATER DRAIN VALVE

CONTACTOR COIL

FIG. 8

2. Follow the procedures as per cleaning water pump operation, only by keeping pushed Reset button between 2 ÷ 5" during water filling. Just shorting the operation of the water pump to 10 minutes.

3. Place again the evaporator cover and the unit service panels.

4. At completion of the freezing and harvest cycle make sure of proper texture and clearness of the ice cubes and that, they do not have any acid taste.

ATTENTION. In case the ice cubes are cloudy-white and have an acid taste, melt them immediately by pouring on them some warm water. This to prevent that somebody could use them.

5. Wipe clean and rinse the inner surfaces of the storage bin.

REMEMBER.

To prevent the accumulation of undesirable bacteria it is necessary to sanitize every week the interior of the storage bin.

Scotsman AC-EC 57, AC-EC 47, AC-EC 127, AC-EC 87, AC-EC 177 Service Manual

Specifications and Main Features

Frequently Asked Questions

User Manual