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Removal and Replacement: Refrigeration System

General:

Scotsman recommends that any work on the
refrigeration system only be done when it is certain
that the system needs repair. 

••

Refrigerant should not be added except as a
way to determine the proper operation of the
product. If the system was low on refrigerant,
there is a leak, and it must be found and
repaired.

••

Refrigerant must not be wasted to the
atmosphere, but recovered.

••

This system has a critical charge, it must be
recharged with the correct amount of refrigerant
as listed on the nameplate of the ice machine,
or performance will suffer.

••

Anytime the refrigeration system has been
opened, the dryer should be replaced.

••

When brazing the tubing connections to the
thermostatic expansion valve, the component
must be protected by heat sink material.

••

If the air cooled condenser must be replaced,
the unit will have to be removed from its
installed location, and the back panel removed
to gain access.

Specifically:

Recover, reclaim or recycle refrigerant. The
method chosen is up to the service company.
There are various mechanical devices that may be
used to recycle refrigerant at the field level,
however, Scotsman requires that any refrigerant
placed into a Scotsman ice machine meet ARI
spec 700. Reclaim programs are available thru
most refrigerant wholesalers. 

Use conservation minded service procedures: 

••

Refrain from checking refrigeration pressures
without reason. There are many ways to
determine the proper operation of a Scotsman
ice machine without using refrigerant gauges.
Visual inspection of the water system,
observation of the ice formation, amp draw,
voltage, and other techniques will lead to proper
diagnosis. Scotsman also recommends that, at
the time of initial start up, gauges not be used.

••

If gauges must be used, do not always check
the high side pressure. If the condenser is clean
and seems to be operating correctly, it most
likely is. The low side pressure is much more
important on an ice machine than is the high
side. 

••

If gauges must be used, use very short hoses.
Minimal refrigerant discharged into the hoses
equals minimal refrigerant discharged into the
air. 

••

If using recycled refrigerant, it must meet ARI
spec 700 or have been cleaned by a machine
capable of attaining ARI spec 700. Removal
and Replacement: Refrigeration System

AF300

January 1993

Page 25

Summary of Contents for AF300

Page 1: ...ssis to allow service access without removing the ice machine from its installed location The refrigeration system uses R 22 as the refrigerant Table of Contents Specifications page 2 Limitations page 3 Installation page 4 Plumbing page 5 Final Check List page 6 Cabinet Removal page 7 Component Location page 8 Electrical Sequence page 9 Initial Start Up page 10 Cleaning page 11 Water Schematic pag...

Page 2: ...ctrical Ice Type Condenser Type Typical Amps Maximum Fuse Refrigerant AF300AE 1A 33 x 241 4 x 24 115 60 1 Flake Air 9 15 R 22 AF300WE 1A 33 x 241 4 x 24 115 60 1 Flake Water 9 15 R 22 A scoop and legs 6 are included The nameplate is located on the back panel A serial number plate is located behind the right grill in front of the control box on the base SERIAL NUMBER PLATE AF300 January 1993 Page 2...

Page 3: ... CSA Scotsman assumes no liability or responsibility of any kind for products manufactured by Scotsman that have been altered in any way including the use of any part and or other components not specifically approved by Scotsman Scotsman reserves the right to make design changes and or improvements at any time Specifications and design are subject to change without notice Airflow on air cooled mod...

Page 4: ... out suspended solids to a dimension of 5 microns or less The finer the filter the better but finer filters may plug up sooner than course ones It may be necessary to add a course filter ahead of the fine filter to prolong filter life Have the water tested Either acidic water or alkaline water will cause corrosion Dissolved solids cannot be filtered out Check with a water treatment specialist rega...

Page 5: ...rial must be rigid and meet local code Traps in the bin drain line without vents ahead of them will cause poor draining The bin drain must be vented if there is a long horizontal run 5 or more All drains are gravity and must have a minimum fall of 1 4 per foot of horizontal run Maintain the air gap required by local code between the end of the drain tubes and the building drain receptacle Drain tu...

Page 6: ...maker cabinet in a room where ambient temperatures are within the minimum and maximum temperatures specified 2 Has the water supply been connected 3 Is the water pressure adequate 4 Have the water connections been checked for water leaks 5 Have the drain connections been made 6 Have the drain connections been checked for leaks 7 Is the cabinet level 8 Is the ice machine plugged into a 115 volt ele...

Page 7: ...until it can be lifted up Caution the door may be free to come out the back of the hood when removed from the cabinet base 4 To remove the cabinet base the hood must be removed first 5 Remove 4 screws and the two grills at the front of the base 6 In the area exposed when the grills are removed are two knobs similar to those removed in step 2 Unscrew and remove the two knobs 7 Locate bin drain Loos...

Page 8: ...ally closed when the machine is operating If the low side pressure should drop too low the control will open at 0 4 PSIG stopping the ice maker It is an automatic reset High Pressure Control The pressure switch is designed to open and shut off the machine should the high side refrigeration pressure become too high usually as a result of not enough water through the water cooled condenser It is a m...

Page 9: ... the compressor starts and the low side pressure drops The next control the power is connected to is the Low Water Pressure Control This switch is designed to open should the water pressure to the machine drop too low The next control is the Bin Thermostat It is closed when there is no ice on the portion of the control inside the thermostat bracket It is open when there is ice on the portion of th...

Page 10: ...tes Then pour clean water into the bin to melt the ice This will flush out most manufacturing or shipping materials that may have strayed into the water ice making system 7 Check the operation of the bin thermostat by placing ice over the sensing tube A properly operating bin thermostat will open when ice covers the sensing tube When the bin thermostat opens the compressor will stop but the auger ...

Page 11: ... cold water or if torn or so dirty it can t be cleaned replace with a new filter 5 Return the filter to its installed position 6 Replace the bracket removed in step 2 7 Replace the grill Do not operate the unit without the filter in place Note If the unit has been operated without the filter in place the fins of the condenser will become fouled with dirt and must be cleaned Scotsman recommends tha...

Page 12: ...ve the master switch to ON continue to pour cleaning solution into the reservoir until it has all been used 17 After all of the solution has been poured in remove the block from under the float 18 Operate the unit for 15 more minutes and then taste the ice if not sour tasting all of the ice machine cleaner has been used up Do not go to the next step until the ice has no sour taste 19 Pour clean wa...

Page 13: ...x sanitizing solution of 1 ounce of household bleach to 2 gallons of water 2 Using clean rubber gloves and a clean cloth wipe all interior surfaces of ice storage bin hood and door with sanitizing solution Be sure and wipe the joint between the hood and bin with the sanitizing solution Use a clean brush to thoroughly swab all interior surfaces with the sanitizing solution 3 Reassemble and allow to...

Page 14: ... Note The auger can t be pulled out when the unit is installed under the counter 1 Remove the hood door and ice storage bin 2 Remove stainless steel cover plate 3 Remove cover from reservoir and block the float or shut off the water supply 4 Locate evaporator drain and drain the evaporator reservoir 5 Remove O ring holding insulation halves together at the top of the evaporator 6 Remove insulation...

Page 15: ...rator the water chills into ice crystals and is pushed up the evaporator by the auger At the top of the evaporator the ice is pressed against a restriction called a breaker and some of the water is squeezed out of the crystalline ice The flaked ice then flows through the chute into the bin WATER SCHEMATIC STRAINER WATER SAFETY SWITCH RESERVOIR OVERFLOW DRAIN RESERVOIR EVAPORATOR DRAIN BIN DRAIN EV...

Page 16: ...ic expansion valve the liquid refrigerant passes from a high pressure zone to one of relatively low pressure and in the low pressure zone it evaporates The low pressure zone where the refrigerant evaporates is the evaporator When the refrigerant evaporates it absorbs heat from the metal parts of the evaporator and the water inside it From the evaporator the refrigerant flows back to the compressor...

Page 17: ...Fan Motor 16 watt rating 1500 RPM CW Water Cooled Fan Motor 5 watt rating 1500 RPM CW Compressor Copelaweld hermetic model JSS5 0050 IAA capacitor start induction run Gearmotor 1 10 H P shaded pole motor 11 RPM output shaft speed Gearmotor amps will be about 2 8 3 2 Bin Thermostat 45o F cut in 35o F cut out minimum 61o F cut in 51o F cut out maximum Water Pressure Switch 10 PSI Cut Out 20 PSI Cut ...

Page 18: ...essure the low pressure cut out opens at pressure below 4 psig If open it may be due to a the evaporator is too cold because the auger was not turning when the unit was refrigerating b there is not enough refrigerant c there is a restricted system Check a b or c below If a Check the coupling if it s turning and the auger isn t replace the coupling If the coupling is not turning remove the gearbox ...

Page 19: ...place those items found defective STATUS MAKES ICE BUT ALSO MAKES EXCESSIVE NOISE A Check if the unit has been cleaned recently it will make extra noise if minerals have stained the auger and or evaporator Clean it if in doubt B Check the coupling by greasing it C Check the bearings for wear D Check the evaporator for wear There are vertical ice guide marks machined into the evaporator s interior ...

Page 20: ... controls posts 6 Follow the capillary tube of the bin thermostat and remove it from the grommet in the back of the control box 7 Pull the end of the bin thermostat from the tube holder 8 Pull the capillary back through the grommet in the evaporator bracket until free Remove the bin thermostat from the ice machine 9 Reverse the above steps to replace Water on the capillary tube will make the insta...

Page 21: ...r of the auger so that when the water seal is placed on the auger the gap between the auger shoulder and the water seal is completely filled with the sealant 4 Clean the inside of the evaporator at the bottom bearing and water seal mounting area Lubricate the outside edge of the stationary seal with water 5 Carefully push the stationary part of the water seal up into the bottom of the evaporator I...

Page 22: ...tor and reservoir cover plate 3 Unscrew the bolts holding the gearmotor mounting plate to the ice machine chassis 4 Use a 1 2 box wrench to unscrew the three cap screws holding the evaporator to the gearmotor 5 Remove the motor and centrifugal switch electrical leads from their connections 6 Raise the evaporator assembly up enough that the output shaft clears the freezer adaptor 7 Remove the gearm...

Page 23: ...e cover and torque at 80 90 inch pounds 4 Bench test the gearmotor assembly Test for noise amp draw must not be in excess of ice maker nameplate for gearmotor and oil leaks Return the gearmotor assembly to the unit Be certain all mounting surfaces are clean and reassemble to the gearmotor mounting plate Then bolt back onto ice machine chassis GEARMOTOR PARTS MOTOR HOUSING FAN STATOR ROTOR FIBER GE...

Page 24: ... Raise the evaporator assembly up enough that the output shaft clears the freezer adaptor and remove the evaporator from the ice machine 12 After the evaporator has been removed from the ice machine the auger and bearings may be removed The fasteners auger breaker cover and insulation halves should be saved for use in the new evaporator New bearings and a water seal will be required when replacing...

Page 25: ...arious mechanical devices that may be used to recycle refrigerant at the field level however Scotsman requires that any refrigerant placed into a Scotsman ice machine meet ARI spec 700 Reclaim programs are available thru most refrigerant wholesalers Use conservation minded service procedures Refrain from checking refrigeration pressures without reason There are many ways to determine the proper op...

Page 26: ...uum pump to 500 microns or less If the triple evacuation method is used the vacuum should be broken each time with dry nitrogen not refrigerant Evacuation must be from both sides of the system Weigh in or measure in the nameplate charge Recharge into the high side Check for leaks with a high quality electronic leak detector Halide torches will not locate the very small leaks If an ice machine is t...

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