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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. 

••

The access valves are at the front of the
cabinet. To use them, remove the cap from the
valve ports and the cap from the top of the
valve body. Attach gauge manifold and then
use a 3/16" allen wrench to loosen the valve.
Although pressure readings may be taken with
the valve cracked open, several turns are
required to completely open the valve. Close
the valve and replace the caps when the job
is finished.

••

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 vented to the
atmosphere.

••

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 hot
gas or thermostatic expansion valve, the
component must be protected by heat sink
material.

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 700-88. Reclaim programs are available
through 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 production, 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
700-88 or have been cleaned by a machine
capable of attaining ARI spec 700-88. 

ALLEN

WRENCH

Torque Stem

to 6-8 ft. lbs.

Torque Cap to

8-12 ft. lb..

ACCESS

VALVE

Torque Cap to

7-12 ft. lb..

NM1852

August  1993

Page 31

Содержание NM1852

Страница 1: ...ctronic circuit for monitoring ice and water level a thermostatic expansion valve and R 22 as the refrigerant TABLE OF CONTENTS Installation For the Installer Specifications 2 Storage Bin 4 Location 5...

Страница 2: ...me Basic Electrical 208 230 60 1 same 208 230 60 3 same Ice Type NUGGET same same same Condenser Type Air Water Air Water The normal finish for the ice machine is enamel sandalwood A stainless steel p...

Страница 3: ...water test and recommendations regarding filters and treatment 2 In most cases the water used to make ice should be filtered or treated depending upon the water There is no one type of water filter th...

Страница 4: ...urn the leg levelers all the way in preparation for leveling later Return the bin to the upright position remove paper covering the bin gasket Note Do not push bin into position but lift it there Push...

Страница 5: ...FOR THE INSTALLER Location ALLOW ROOM FOR AIR CIRCULATION AND SERVICE ACCESS DO NOT STACK ANYTHING IN FRONT OF THE MACHINE S NM1852 August 1993 Page 5...

Страница 6: ...r cooled condensers The water pressure to all lines must always be above 20 psig and below 80 psig Drains Air Cooled Models There is one 3 4 FPT drain for both ice making systems at the back of the ca...

Страница 7: ...machine requires a solid chassis to earth ground wire The ice maker should be connected to its own electrical circuit so it would be individually fused Voltage variation must remain within design limi...

Страница 8: ...ate requirements 3 Have all the plumbing connections been made and checked for leaks 4 Has the machine and bin been leveled 5 Is there a minimum of 6 clearance at the back of the machine for proper se...

Страница 9: ...ed into the drain 5 The unit should soon be making ice if desired the low side pressure of each system can be checked it should be 25 psig or 2 PSIG The suction line temperature at the compressor is n...

Страница 10: ...the reservoir to make ice out of Will shut the machine off it there is none Ice Discharge Chute Directs the ice produced by the evaporator into the storage bin Ice Level Sensor An electronic eye it se...

Страница 11: ...a built in time delay to clear the evaporator of ice when the unit turns off and for the compressor Transformer Supplies low voltage to the circuit board Low Pressure Cut Out Switch A manual reset con...

Страница 12: ...ere the two seal faces meet Ice Sweep A plastic cap with fingers It revolves with the auger to sweep the ice into the ice chute Breaker Divider Where the ice is compressed and much of the extra water...

Страница 13: ...Shut Down consists of The compressor relay opens The compressor contactor opens The compressor stops The auger motor is run by the circuit board for 2 more minutes clearing out ice in the evaporator...

Страница 14: ...m of each evaporator Reservoir overflow or evaporator condensation is routed to the drain Water cooled models have a separate water circuit for the cooling water it enters the fitting at the rear divi...

Страница 15: ...r evaporators get more refrigerant and colder evaporators get less At the evaporator the refrigerant enters an area of relatively low pressure where it can easily boil off or evaporate As it evaporate...

Страница 16: ...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 7 Prepare the c...

Страница 17: ...o be checked at least two times per year A Check the bearing by removing the ice chute cover unscrewing the ice sweep removing the water shed unscrewing the breaker cover unscrewing the auger stud Ins...

Страница 18: ...locating pins and out of the unit B Remove two screws and unplug the fan motors D Clean the condenser reassemble by placing the fan motor assembly onto the locating pins replacing the mounting screws...

Страница 19: ...off electrical power and water supply 1 To remove the auger remove the front and top panels 2 Remove 3 hex studs holding ice chute cover to ice chute and remove cover 3 Unscrew and remove ice sweep 4...

Страница 20: ...the drier evacuate and weigh in the nameplate charge E Check the high pressure cut out if closed go to F if open check 1 The pressure control opens at 400 psig Check the high side pressure reset the c...

Страница 21: ...full light on the tester should be ON if not replace the circuit board If the bin full light on the tester is ON move the tester switch to bin empty the light on the tester should go OFF and the bin...

Страница 22: ...il is open replace the contactor 3 Check the auger drive motor centrifugal switch If when the drive motor is running contact 4 black wire removed has no power and all of the above switches have been c...

Страница 23: ...leaks replace the water seal if found to be leaking 3 Check the low side pressure normal is about 25 psig If low assume a refrigerant leak locate recover repair and recharge If no leak the TXV may be...

Страница 24: ...emaker 8 Reverse to reassemble BIN CONTROLS Ice Level Sensors 1 Disconnect electrical power 2 Remove front panel 3 Remove control box cover 4 Locate ice chute at the base of the chute in front of and...

Страница 25: ...reaker to evaporator d Lift up and remove breaker bearing assembly from auger evaporator 6 Service the bearing Check for rust rough spots and damage a The bearing is pressed into the breaker to remove...

Страница 26: ...threads b Unscrew auger stud from top of auger c Unscrew 4 allen head cap screws holding breaker to evaporator d Lift up remove breaker from evaporator e If the auger is stuck use a slide hammer type...

Страница 27: ...n against it 3 The part of the water seal that rotates with the auger must also be replaced Remove the old part from the auger and clean the mounting area 4 Place a small bead of food grade silastic s...

Страница 28: ...ted then weigh in the nameplate charge Check for leaks 8 Install auger breaker breaker bearing assembly and ice discharge chute in reverse order of disassembly See To Reassemble Evaporator and Auger T...

Страница 29: ...tor 2 Unscrew the 4 cap screws holding the gearmotor to the base of the machine 3 Remove the gearmotor from the icemaker Bench test the gearmotor check for oil leaks noise and amp draw To Inspect the...

Страница 30: ...bolts from top end of fan motor assembly see the illustration 4 Lift up and pull out the fan motor assembly 5 Repair as needed 6 To reassemble Place the fan motor assembly lower flange holes over the...

Страница 31: ...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...

Страница 32: ...the tester into the circuit board 3 Unplug water sen connector from control board 4 Plug water sen connector from Scotsman tester into circuit board Bin Level a Move the bin full switch on the tester...

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