Scotsman FME1204R, NME954R Service Manual

INTRODUCTION
NME954R & FME1204R
To the owner or user: The service manual you are reading is intended to provide you, and the maintenance or service technician, with the information needed to install, start up, clean, maintain, and service this ice system.
The ice machines covered in this manual are a remote condenser type modular ice system that fits a variety of Scotsman storage bins. They feature: front service for the freezer, gear motor, control box, water reservoir, and bin control; an electronic circuit for monitoring ice and water level; a thermostatic expansion valve; and R-404A as the refrigerant.
Table of Contents
FOR THE INSTALLER ······································ Page 2 REMOTE CONDENSER SPECIFICATIONS ··························· Page 3 FOR THE INSTALLER ······································ Page 4 Remote Condenser Location ··································· Page 5 FOR THE INSTALLER: Remote Condenser ··························· Page 6 FOR THE INSTALLER: Coupling Instructions ·························· Page 7 FOR THE INSTALLER: Location ································· Page 8 FOR THE PLUMBER ······································· Page 9 FOR THE ELECTRICIAN ····································· Page 10 FOR THE ELECTRICIAN: Fan Relay Kit ···························· Page 11 FOR THE INSTALLER: Completed Installation ·························· Page 12 FOR THE INSTALLER: Final Check List ····························· Page 13 START UP ············································ Page 14 COMPONENT DESCRIPTION ·································· Page 15 COMPONENT DESCRIPTION: Control Box ··························· Page 16 ELECTRICAL SEQUENCE: ··································· Page 17 OPERATION: Water ······································· Page 18 OPERATION: Refrigeration ···································· Page 19 OPERATION: Refrigeration ···································· Page 20 MAINTENANCE AND CLEANING ································ Page 21 Sensor Maintenance ······································· Page 22 Bearing Maintenance ······································· Page 23 Auger Maintenance ········································ Page 24 SERVICE DIAGNOSIS: No Ice ·································· Page 25 SERVICE DIAGNOSIS: Low Capacity ······························ Page 26 CONTROL SYSTEM DIAGNOSTICS ······························ Page 27 REMOVAL AND REPLACEMENT: Water Reservoir & Bin Controls ··············· Page 28 REMOVAL AND REPLACEMENT: Bearing and Breaker ···················· Page 29 REMOVAL AND REPLACEMENT: Auger ···························· Page 30 REMOVAL AND REPLACEMENT: Water Seal ·························· Page 31 REMOVAL AND REPLACEMENT: Evaporator ·························· Page 32 REMOVAL AND REPLACEMENT: Gear Motor Assembly ···················· Page 33 Refrigeration Service ······································· Page 34
Parts Lists and Wiring Diagrams are located in the center of this manual.
January 2000
Page 1
This Manual Was Printed
On Recycled Paper
NME954R & FME1204R
FOR THE INSTALLER
Either the FME1204R or the NME954R is designed to fit the following Scotsman storage bins:
SB480 and extensions (with bin top KBT18)
·
BH800 using bin top KBT15 (one unit) or KBT25
·
(two units).
BH801 using bin top KBT28
·
BH900 with KBT24 (one unit)
·
BH900 with KBT25 (two units side by side)
·
Allow 6" above machine
for service.
NME954 Dispenser Applications
The NME954 can be placed on and used with certain ice and ice-beverage dispensers. Kits are required for proper operation:
Back View
ID150 use adapter KBT42 and KNUGDIV
·
ID200 or ID250, use adapter KBT46 and
·
KDIL-N-ID2
Cornelius ED/DF200 beverage dispensers, use
·
KBT46 and KDIL-N-200
Cornelius ED/DF250 beverage dispensers, use
·
KBT46 and KDIL-N-250
Lancer nugget IBD, use KDIL-N-L & Lancer kit.
·
Liquid Line Connection
Discharge Line Connection
Remote Condenser
Junction Box
Electrical Inlet
20.84"
2.96"
Drain
3/4" FPT
SPECIFICATIONS: ICE MAKER
Model Number Dimensions
(w/o bin)
H”xW”xD” FME1204RS-32A 27 x 21 x 24 208-230/60/1 FLAKE Remote Air 14.1 20 208 ounces FME1204RS-3A same 203-230/60/1 FLAKE Remote Air 11.2 15 208 ounces NME954RS-32A same 208-230/60/1 NUGGET Remote Air 14.1 20 208 ounces NME954RS-3A same 208-230/60/3 NUGGET Remote Air 11.2 15 208 ounces
Minimum Circuit Ampacity is used to determine wire size and type per National Electric Code.
Basic Electrical Ice Type Cond. Type Minimum
Water Inlet
3/8" Flare
5.25"
3"
Circuit Ampacity
Maximum Fuse Size
Refrigerant Charge (R-404A)
January 2005
Page 2
NME954R & FME1204R
REMOTE CONDENSER SPECIFICATIONS
Model Use with Basic Electrical ERC151-32 1 FME1204R or 1 NME954R 208-230/60/1 ERC302-32 1 or 2 FME1204Rs or NME954Rs SAME
2.00
5.08
ERC DIMENSIONS
19.75
50.17
ABFG
3
33
"10
8
3
"16
4
3
"11
4
5
"
8
Liquid Line .38 Quick Connect Fitting .95
2.75
14.53
Air Discharge
Air Intake
Other Required Items:
RTE25 Precharged line set, 25’, R-404A or
Discharge Line .50 Quick Connect Fitting
1.27
Adjustable Roof Clearance
12.00 18.00 24.00
30.48 45.72 60.95
2.07
23
19
13
"
16
7
"
8
.53
1.35
(6)
RTE40. Precharged line set, 40’, R-404A.
ICE MAKER NAMEPLATE
LOCATED ON BACK PANEL
SERIAL PLATE LOCATED
BEHIND FRONT PANEL
January 2000
Page 3
NME954R & FME1204R
FOR THE INSTALLER
Installation Limitations:
The machine and bin are designed to be installed indoors, in a controlled environment:
Min Max
0
Air Temperature 50
(Not including the remote condenser)
Water Temperature 40
Water Pressure (PSI) 20 80
Voltage 198 253
(Compared to the nameplate)
Operating the machine outside of the limitations is misuse and can void the warranty.
Scotsman Ice Systems are designed and manufactured with the highest regard for safety and performance. They meet or exceed the standards of UL, NSF, and CUL.
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.
F 1000F
0
1000F
Location
Install the machine in a location where it has enough space around it to be accessible for service, usually a minimum of 6 inches. Try to avoid hot, dirty and crowded locations. Be sure that the location for the machine is within the limitations.
Storage Bin
Tip the storage bin on its back, using parts of the carton to protect the exterior finish. Install the legs into the threaded holes in the bottom of the bin. Turn the leg levelers all the way in preparation for leveling later. Return the bin to the upright position, remove paper covering the bin gasket.
Install the bin top according to the directions with the bin top.
Note: Do not push bin into position, instead lift it there. Pushing a bin, especially one with ice in it, can cause damage to the legs and the leg mounts.
Ice Maker
The machine is heavy, so the use of a mechanical lift is recommended for lifting the machine high enough to install on top of the bin. After the unit is placed on the bin, line it up so it is even with the back side. Secure the machine to the bin with the hardware provided with the machine.
Remove the front panel and remove any shipping blocks.
Note: Be sure to allow a 6" minimum space above the top of the machine for service.
January 2000
Page 4
Remote Condenser Location
NME954R & FME1204R
Use the following for planning the placement of the condenser relative to the ice machine
Location Limits - condenser location must not exceed ANY of the following limits:
Maximum rise from the ice machine to the
·
condenser is 35 physical feet
Maximum drop from the ice machine to the
·
condenser is 15 physical feet
Physical line set maximum length is 100 feet.
·
Calculated line set length maximum is 150.
·
Calculation Formula:
Drop = dd x 6.6 (dd = distance in feet)
·
Rise = rd x 1.7 (rd = distance in feet)
·
Horizontal Run = hd x 1 (hd = distance in feet)
·
Calculation: Drop(s) + Rise(s) + Horizontal Run
·
= dd+rd+hd = Calculated Line Length
Configurations that do NOT meet these requirements must receive prior written authorization from Scotsman.
Do NOT:
Route a line set that rises, then falls, then rises.
·
Route a line set that falls, then rises, then falls.
·
Calculation Example 1:
The condenser is to be located 5 feet below the ice machine and then 20 feet away horizontally.
5 feet x 6.6 = 33. 33 + 20 = 53. This location would
be acceptable
Calculation Example 2:
The condenser is to be located 35 feet above and then 100 feet away horizontally.
35 x 1.7 = 59.5. 59.5 +100 = 159.5. 159.5 is
greater than the 150 maximum and is NOT acceptable.
rd
22.87"
dd
17.15"
Remote
Condenser
Located ABOVE
Ice Machine
Remote
Condenser
Located BELOW
Ice Machine
hd
40.35"
Condenser Distance and Location Schematic
January 2000
Page 5
NME954R & FME1204R
FOR THE INSTALLER: Remote Condenser
Location
Select the best available location, protecting the condenser from extremes of dirt, dust, and sun.
Meet all applicable building codes. Usually the services of a licensed electrician are required.
Roof Attachment
1. Install and attach the remote condenser to the roof of the building, using the methods and practices of construction that conform to the local building codes, including having a roofing contractor secure the condenser to the roof.
2. Have an electrician connect the remote condenser fan motor to the ice maker, using the junction box at the back of the ice maker.
PRECHARGED LINE ROUTING
CAUTION
Do not connect precharged tubing until all routing and forming of the tubing is complete. See the coupling instructions for connecting information.
5. Have the roofing contractor seal the holes in the roof per local codes.
Note: Precharged tubing contains a R-404A holding charge. The entire refrigerant charge required for the system is contained in the ice machine.
Tubing illustration shows tight spiral; a spiral in the field depends on tubing limitations. Tight spiral not required.
REMOTE CONDENSER
1. Each set of precharged refrigerant lines (either 25 foot or 40 foot) consists of a 3/8 inch diameter liquid line and a 1/2 inch diameter discharge line. Both ends of each line have quick connect couplings, one end has a schrader valve connection, that end goes to the condenser.
Note: The openings in the building ceiling or wall, listed in the next step, are the minimum sizes recommended for passing the refrigerant lines through.
2. Have the roofing contractor cut a minimum hole for the refrigerant lines of 1 3/4 inch. Check local codes, a separate hole may be required for the electrical power to the condenser.
CAUTION
DO NOT KINK OR CRIMP REFRIGERANT TUBING WHEN INSTALLING IT.
3. Route the refrigerant lines through the roof opening.
Follow straight line routing whenever possible.
Spiral Excess Tubing
Inside
Building
Remote Condenser
Above Ice Maker
Any excess tubing MUST be retained within the building.
4. Spiral the excess length of pre charged tubing inside the building. Use a horizontal spiral (as illustrated) to avoid any traps in the lines.
January 2000
Page 6
NME954R & FME1204R
FOR THE INSTALLER: Coupling Instructions
4b. Using two wrenches, one to rotate the swivel
Note: The couplings on the sets of precharged lines must be installed properly to prevent leaking. Carefully follow the instructions:
Initial Connections:
1. Remove the protector caps and plugs. Wipe the seats and threaded surfaces with a clean cloth to be certain that no foreign matter remains on them.
2. Lubricate the inside of the couplings, especially the O-Rings with refrigerant oil.
3. Position the fittings on the correct connections on the condenser and ice machine.
nut and one to hold the tubing, tighten each coupling.
It is CRITICAL that ONLY the NUT on the pre-charged tube be turned or the diaphragms will be torn loose by the piercing knives and be loose in the refrigeration system causing severe operational problems.
Tighten Swivel Nut
Clean and Lubricate Couplings
·
The ½ inch discharge line (schrader valve end) goes to the remote condenser fitting marked “discharge line.”
3
·
The
inch liquid line (schrader valve end) goes
8
to the remote condenser fitting marked “liquid line.”
·
The ½ inch discharge line goes to the ice maker fitting marked “discharge line.”
3
·
The
inch liquid line goes to the ice maker
8
fitting marked “liquid line.”
Final Connections:
4a. Begin by tightening the couplings together by hand. Continue to turn the swivel nuts by hand until is is certain that the threads are properly engaged.
Note: As the coupling is tightened, the diaphragms in the quick connect couplings will begin to be pierced. As that happens, there will be increased resistance to tightening the swivel nut.
4c. Continue tightening the swivel nut until it bottoms out or a very definate increase in resistance is felt (no threads should be showing). Do NOT overtighten.
5. Using a marker or pen, mark a line lengthwise from the coupling union nut to the bulkhead. Then tighten the coupling and additional 1/4 turn. As the nut turns, the line will show when 1/4 turn is made.
6. After all connections are made, and after the king valve has been opened (do not open at this time), check the couplings for leaks.
Schrader
Valve
TO REMOTE
CONDENSER
No Schrader
Valve
Rotate Swivel Nut ¼ Turn More
TO ICE MAKER
January 2000
Page 7
NME954R & FME1204R
FOR THE INSTALLER: Location
EXCESS
PRECHARGED
TUBING INSIDE
BUILDING
TWO UNITS ON ONE CONDENSER
REMOTE
CONDENSER
ROOF
CUTAWAY
ICE MAKERS
SERVICE
ACCESS
SERVICE ACCESS
SIDE AND BACK
WALL
CUTAWAY
January 2000
Page 8
FOR THE PLUMBER
CONFORM TO ALL APPLICABLE CODES
NME954R & FME1204R
Water Inlet
Field Supplied
Hand Shut
Off Valve
Water Filter
Connect To Cold Water
Water Inlet
3/8" Male Flare
Vent Ice
Maker
Drain, 3/4"
FPT
Connect a cold potable water supply to the ice machine. Use 3/8" O.D. copper tubing and connect it to the 3/8" male flare at the back of the cabinet.
Install a hand valve near the machine to control the water supply.
Drains
The cabinet has a ¾" FPT drain. connection. The drain is at the back of the cabinet, the drain line is of the gravity type, and 1/4 inch per foot fall is an acceptable pitch for the drain tubing. There should be a vent at the highest point of the drain line, and the ideal drain receptacle would be a trapped and vented floor drain. Use only ¾" rigid tubing.
Storage Bin: Install a separate gravity drain to the ice storage bin. Insulation of this drain line is recommended.
Vent Bin Drain
3/4" FPT
Floor Drain
January 2000
Page 9
NME954R & FME1204R
FOR THE ELECTRICIAN
CONFORM TO ALL APPLICABLE CODES
Connect the electrical power to the ice machine through the junction box at the back.
Check the nameplate (located on the back panel) for the voltage requirements, and for the minimum circuit ampacity. The 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 limitations, even under starting conditions.
Terminal Strip For
Remote
Condenser
Ice Maker
Junction Box
Electrically the remote condenser fan motor is connected to the ice maker at the contactor terminals for the compressor and the fan motor operates whenever the compressor operates.
Electrical connections are made at the junction box at the back of the ice maker and at the junction box on the remote condenser.
The remote condenser must be wired to the ice maker in accordance with local and national electrical codes with a minimum of 18 Awg. wire with an ground bonding wire connected to the ground screws provided in both the condenser and machine field wiring boxes. All outdoor wiring must be in rain proof conduit.
All external wiring must conform to national, state, and local electrical codes. The use of a licensed electrician is required to perform the electrical installation.
Ground The
Chassis
Power
Supply
Rain Proof Conduit
January 2000
Page 10
FOR THE ELECTRICIAN: Fan Relay Kit
NME954R & FME1204R
WARNING
Do all wiring with the electrical power disconnected.
To install the KCMR230 fan relay kit when using (2) 230 VOLT ice makers and one 230 volt, two circuit remote condenser (ERC302).
See the remote condenser nameplate for current requirements to determine wire size to be used for electrical hookup. Refer to wiring diagram.
All external wiring should conform to the national, state and local electrical codes. Usually an electrical permit and services of a licensed electrician will be required.
1. Mount the control box in a convenient location.
2. Attach a solid earth ground wire to the ground screw.
3. Route connecting wires from the first ice maker junction box
(marked condenser fan) and connect it to the KCMR230 terminal strip marked: NO. 1 ICE MACHINE.
4. Route connecting wires from the second machine junction box
(marked condenser fan) and connect it to the KCMR230 terminal strip marked: NO. 2 ICE MACHINE.
5. Route connecting wires from KCMR230 terminal strip marked: TO REMOTE FAN and connect at the remote condenser junction box.
6. Check phasing of the electrical circuit as follows:
A. The phasing of the wiring MUST now be checked, as incorrect phasing will result in a failure of the kit relay.
Below is an illustration of the KCMR230 terminal strip. Note that each terminal is marked: 1-2-3-4-5-6. For proper phasing:
Terminals #1 and #3 must be connected to the same side of the line (such as L1)
Terminals #2 and #4 must be connected to the same side of the line (such as L2).
B. Make a test with a volt meter as follows:
1. Switch on ice maker #1 first, then switch on ice maker #2.
(The compressors must be operating for this test. Do this after start up.)
2. Test with a volt meter between terminals #2 and #4, then between terminals #1 and #3. Compare the readings obtained to the ones in the following list:
C. Test terminals 1-2 = Full Voltage (208-230)
Possible Location
For KCMR230
Control Box
Test terminals 1-3 = No voltage
Test terminals 2-3 = Full Voltage
Test terminals 2-4 = No voltage
Test terminals 3-4 = Full voltage
Test terminals 1-4 = Full voltage
D. If there is full voltage where there should be no voltage, turn off ice maker #2, (both switches) Then turn off ice maker #1 (both switches). The connections at the KCMR230 terminal strip marked ice maker #1 must be reversed (put the wire that was on 1 on 2 and the wire that was on 2 on 1).
WARNING
Do all wiring with the electrical power disconnected.
January 2000
Page 11
NME954R & FME1204R
FOR THE INSTALLER: Completed Installation
A typical installation should generally appear as illustrated below. The best place for the remote condenser is above the ice machine, although other locations are permisable.
Roof
Cut-Away
Insulated
Precharged
Refrigerant
Tubing
January 2000
Page 12
FOR THE INSTALLER: Final Check List
1. Is the ice system installed indoors in a location where the air and water temperatures are controlled, and where they do not exceed the design limitations?
2. Is there an electrical service disconnect within sight of the installed machine? Has the voltage been checked, and compared to nameplate 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 rear, left, and right of the machine for proper service access?
Remote
Condenser
Secured?
Leveled?
NME954R & FME1204R
Roof Holes
Sealed?
Power
Supply?
6. Is the water pressure a minimum of 20 psig?
7. Has the machine been secured to the bin?
8. If two units on one condenser, has the relay kit been installed?
9. Is there a water shut off valve installed near the machine?
10. Is the remote condenser installed per local building codes, and in a place where it has adequate ventilation and minimal solar heat gain?
11. Has all shipping material and literature (inside the front panel) been removed from the units?
12. Have the remote condenser and precharged lines been properly installed?
13. Has the electrical connection between the ice maker and the condenser been made?
Plumbing?
14. Verify that the master switch is in the OFF position.
15. Switch on the electrical power.
16. Refer to Pre-Start instructions, the next page.
January 2000
Page 13
NME954R & FME1204R
INITIAL START UP
Pre-Start Inspection
1. Remove the front, left, and right side service panels.
2. Check that any shipping blocks have been removed.
3. Inspect the interior of the machine for loose screws or wires. Check that no refrigerant lines are rubbing each other. Check that the fan blade turns freely (remote condenser).
4. Check that the refrigerant lines are properly installed.
5. Check that the electrical power has been on for at least 4 hours and that the compressor dome is warm.
6. Check that the unit is installed correctly according to the final check list on page 13.
Start Up
1. Go through the pre-start inspection.
2. Open the hand valve, observe that water enters the water reservoir, fills the tube from the reservoir to the evaporator, and then shuts off. Check for leaks.
3. Open the King Valve.
4. Turn the master switch on.
The electrical start up sequence is automatic.
There will be a short (15 second) delay before the gear motor starts and the liquid line valve opens.
After the liquid line valve opens the low pressure control will close and the compressor will start.
6. The unit should soon be making ice, if desired the low side pressure may be checked, it should be 32 psig + or - 2 psig. The discharge pressure will depend upon air and water temperatures, but should be between 200 psig and 280 psig.
7. THERE ARE NO ADJUSTMENTS TO MAKE, so replace the panels.
8. Clean and/or sanitize the storage bin interior, wipe off the exterior with a clean, damp cloth.
9 Give the owner/user the service manual, instruct him/her in the operation of the unit, and make sure they know who to call for service.
5. The remote condenser fan turns, and the condenser begins to discharge warm air.
10. Fill out the warranty registration, and mail it to the Scotsman Factory.
January 2000
Page 14
COMPONENT DESCRIPTION
NME954R & FME1204R
Control Box: Contains the electrical controls that
operate the machine.
High Pressure Cut Out: A manual reset switch sensing the high side refrigeration pressure. It is set to shut the machine off at 400 psig.
Pump Down Control: An automatic reset pressure switch connected to the low side of the refrigeration system. Controls the compressor.
Evaporator: A vertical stainless steel tube, refrigerated, and water filled. In it, there is a stainless steel auger.
Reservoir: Float operated, it maintains the water level in the evaporator at a constant level, it also contains the water level sensor.
Control Box
Water Level Sensor: Senses if there is water in
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 senses the presence of ice in the bottom of the ice discharge chute. Operates to turn the ice machine on and off automatically as the level of ice in the bin changes.
Gear Motor: An oil filled, speed reduction gearbox, driving the auger.
Cleaning Drain Tube: When uncapped and lowered, drains the evaporator.
Expansion valve: The refrigerant metering device.
High Pressure
Cut Out
Pump Down
Pressure Switch
Compressor
Expansion Valve
Ice Chute
Water Level
Sensor
Reservoir
Cleaning Drain
Tube
Evaporator
Gear Motor
Ice Level
Sensor
January 2000
Page 15
NME954R & FME1204R
COMPONENT DESCRIPTION: Control Box
Contactor: A definite purpose contactor connecting the compressor and the remote condenser fan motor to the power supply.
Circuit Board: Controlling the ice machine through sensors and relays. The sensors are for ice level and water level. The relays are for the gear motor (with a built in time delay to clear the evaporator of ice when the unit turns off) and for the liquid line valve.
Potential Relay: The compressor start relay.
On/Off (Mode) Switch: Manual control for the
machine.
Control Board
Water OK Light
Power Light
Service Light
Freeze Light
Bin Full
Light
LED1
Compressor
Relay
LED3
January 2000
Page 16
Auger
Relay
ELECTRICAL SEQUENCE:
NME954R & FME1204R
There are 7 indicator lights on the control board:
WTR-OK (Water OK). Green. Normal =
·
Glowing. Glows when there is water in the reservoir.
PWR-OK (Power OK). Green. Normal =
·
Glowing. Glows when the control board has power and is functional.
Service. Red. Normally Off.
·
Freeze. Red. Normally glowing when making
·
ice.
Bin Full. Red. Normally Off when making ice.
·
LED1. White. Located next to the board’s
·
Compressor Relay. Normally Glowing when making ice.
LED3. White. Located next to the board’s Auger
·
Motor Relay. Normally Glowing when making
ice. If the machine is switched off at the mode switch, but is otherwise ready to go, switching the mode switch to ON does the following:
The PWR-OK light glows.
·
If there is water in the reservoir the WTR-OK
·
light glows.
·
After 10 seconds the Freeze, LED1 and LED3
lights glow and the machine starts up.
Start Up:
·
The compressor relay and auger motor relay
become energized, connecting power to the
windings of the auger motor and liquid line valve
coil.
·
The liquid line valve opens, refrigerant flows to
the expansion valve.
·
The pump down pressure switch closes
connecting power to the contactor coil
·
The contactor is energized, connecting power to
the compressor, and the compressor starts.
·
As ice is made it passes between the ice level
sensors but because it is not a continuous
stream it only interupts the sensor’s infrared
beam momentarily. The bin full light remains off
and the machine stays on until ice builds up in
the bin and blocks the path between the
sensors for 6 seconds or longer. When that
occurs the bin full light glows and the machine
shuts down.
Shut Down:
The compressor relay opens, LED1 goes out.
·
The liquid line valve closes, stopping refrigerant
·
flow.
The pump down control opens after the suction
·
pressure falls to its cut out point.
The compressor contactor opens
·
The compressor stops
·
The auger motor stays on for 1 more minute,
·
clearing out ice in the evaporator, and then
The auger motor relay opens, LED3 goes out
·
and the auger motor stops. The liquid line valve will not reopen until 2 minutes or more have passed after the last shut down.
If the path between the ice level sensors remains clear for more than 10 seconds the ice machine will restart.
Control Board Protection Devices
When the water level in the reservoir falls
·
below the water level sensor’s tip, the WTR-OK
light goes out and the machine shuts down.
When water refills the reservoir the WTR-OK
light glows and the machine starts up again.
·
If the auger drive motor current becomes
excessive the liquid line valve and auger drive
motor will be switched Off and the Service light
will blink. The control board will restart the auger
drive motor in 4 minutes. If during the first 60
seconds after restart the auger motor current
stays within limits, the liquid line valve is
reopened and the machine returns to normal
operation. If the auger motor’s current is
excessive within 60 seconds after the restart,
the process will be repeated once more. If
during that try the current is still excessive the
machine shuts down and must be manually
reset. The service light will then be glowing
continuously.
To Reset: Switch the power to the machine OFF and then ON.
Other Protection Devices:
·
If the high pressure cut out switch opens the
machine will stop immediately. It will
automatically reset when the pressure falls
below its cut in point.
·
The mode (on - off) switch is the manual
control for the complete machine, but it is not a
service disconnect.e, but it is not a service
disconnect.
January 2000
Page 17
NME954R & FME1204R
OPERATION: Water
Water enters the machine through the 3/8" male flare at the rear of the cabinet, goes to the water reservoir which it enters through the float valve. The water them goes out the bottom of the reservoir tank to the bottom of the evaporator.
Reservoir overflow or evaporator condensation is routed to the drain.
Water
Inlet
Reservoir
Drain Tube
Water Level
Drain
Water Schematic
January 2000
Page 18
OPERATION: Refrigeration
NME954R & FME1204R
Beginning at the compressor, the refrigerant is compressed into a high temperature gas. The discharge line directs this gas to the condenser. At the remote condenser the gas is cooled by air and it then condenses into a liquid. This high pressure liquid then goes through the liquid line to the head pressure control valve, into the receiver, through the liquid line valve and then through the expansion valve.
The thermostatic expansion valve meters liquid refrigerant into the evaporator, the volume of liquid refrigerant depending upon the temperature of the evaporator; warmer evaporators get more refrigerant and colder evaporators get less.
Refrigeration Schematic
At the evaporator, the refrigerant enters an area of relatively low pressure, where it can easily “boil off” or evaporate. As it evaporates, it absorbs heat from the evaporator and whatever is in contact with it (such as the water inside it). After the evaporator, the refrigerant, now a low pressure vapor, goes through the suction line back to compressor, where the cycle is repeated.
System Information @ 90oF. air and 70oF. water.
Suction pressure: 35 PSIG
·
Discharge pressure: 255 PSIG
·
Minimum Discharge pressure (low temp): 180 PSIG
·
Compressor Amps
3 Phase - 2.8
·
Single Phase - 4.3
·
Remote Condenser
Discharge
Line
Head
Pressure
Control
Valve
Liquid Line
King
Valve
Detail Of Head Pressure
Control Valve
Liquid Line
Valve
Suction
Line
Thermostatic
Expansion Valve
Evaporator
Receiver
Compressor
January 2000
Page 19
NME954R & FME1204R
OPERATION: Refrigeration
Low Condensing Temperature
The refrigeration system under low condenser air temperatures is much the same as it is under higher temperatures, with the exception that the resulting low head pressures cause the head pressure control to close off the liquid line between the condenser and the receiver. This forces more refrigerant into the condenser (with a small amount of discharge gas going into the receiver to maintain
SCHEMATIC OF DISCHARGE PRESSURE
CONTROL VALVE, Normal Temperature
Valve
From
Compressor
Disk
To Receiver
pressure the valve opens up the liquid line from the condenser to the receiver.
SCHEMATIC OF DISCHARGE PRESSURE
CONTROL VALVE, Low Temperature
From
Compressor
To Receiver
From
Condenser
pressure until the head pressure is built back up to the rated gauge pressure of 180 psig). At that
PUMP DOWN
During the pump down cycle (usually initiated by the circuit board de-energizing the liquid line valve) the discharge gases flow through their normal path to the remote condenser, through the head pressure control, and into the receiver. At this point the refrigerant flow is stopped by the closed liquid line valve. This action forces the refrigerant into the receiver and keeps it out of the compressor. The pump down continues until the low pressure control turns the compressor off.
January 2000
From
Condenser
Page 20
NME954R & FME1204R
MAINTENANCE AND CLEANING
It is the USER’S RESPONSIBILITY to keep the ice machine and ice storage bin in a sanitary condition. Without human intervention, sanitation will not be maintained. Ice machines also require occasional cleaning of their water systems with a specifically designed chemical. That chemical dissolves mineral build up that forms during the ice making process. Sanitize the ice storage bin as frequently as local health cods require, and every time the ice machine is cleaned and sanitized.
The ice machine’s water system should be cleaned and santized a minimum of twice per year.
ICE MAKING SYSTEM: In place cleaning
1. Check and clean any water treatment devices, if any are installed.
2. Remove screws and front and top panels.
3. Move the ON-OFF switch to OFF.
4. Remove all the ice from the storage bin.
5. Remove the cover to the water reservoir and block the float up.
6. Drain the water reservoir and freezer assembly using the drain tube attached to the freezer water inlet. Return the drain tube to its normal upright position and replace the end cap.
7. Prepare the cleaning solution: Mix eight ounces of Scotsman Ice Machine Cleaner with three quarts of hot water. The solution should be between 90 and 115 degrees F.
Scotsman Ice Machine Cleaner contains acids.
These compounds may cause burns. If swallowed, DO NOT induce vomiting. Give large amounts of of water or milk. Call Physician immediately. In case of external contact, flush with water. Keep out of the reach of children.
11. After draining the reservoir, as in step 6, wash and rinse the water reservoir.
12. Go thru steps 13-19 to sanitize the ice machine water system.
13. Mix two gallons of sanitizer solution. Use an approved sanitizer.
A possible sanitizer solution may be obtained by mixing two gallons of warm (90-115
o
F.) potable
water with 1 ounce of household bleach.
14. Slowly pout the sanitizer solution into the water reservoir until the float rises, then switch the master switch ON.
15. As the ice machine uses water from the reservoir, continue to pour the sanitizer solution into the reservoir.
1
16. After
of the sanitizer solution has been added
2
to the reservoir, and the reservoir is nearly empty, switch the master switch OFF.
17. Drain the reservoir and thoroughly wash the interior of the reservoir and cover with sanitizer solution. Be sure the drain hose is upright and capped.
18. Remove the block from the float in the water reservoir.
19. Switch the master switch to ON
20. Continue ice making for at least 15 minutes, to flush out any cleaning solution.
DO NOT USE any ice produced from the cleaning solution. Be sure no ice remains in the bin.
8. Slowly pour the cleaning solution into the water reservoir until it is full. Wait 15 minutes, then switch the master switch to ON.
9. As the ice maker begins to use water from the reservoir, continue to add more cleaning solution to maintain a full reservoir.
10. After all of the cleaning solution has been added to the reservoir, and the reservoir is nearly empty, switch the master switch to OFF.
January 2000
21. Remove all ice from the storage bin.
22. Add warm water to the ice storage bin and thoroughly wash and rinse all surfaces within the bin.
23. Sanitize the bin interior by washing the interior of the bin with the balance of the sanitizer solution.
24. Switch the master switch ON.
25. Return all panels to their original positions.
Page 21
NME954R & FME1204R
Sensor Maintenance
1. The bin control uses devices that sense light, therefore they must be kept clean enough so that they can “see”. At least twice a year, remove the bin control sensors from the base of the ice chute, and wipe the inside clean, as illustrated.
Ice Chute
Ice Level
Sensors
Slide Left To
Remove
2. The ice machine senses water level by a probe located in the water reservoir. At least twice a year, the probe should be removed from the reservoir, and the tip wiped clean of mineral build-up.
3. Clean the remote condenser. Use a vacuum cleaner or coil cleaner if needed.
Do NOT use a wire brush.
4. Check and tighten all bolts and screws.
January 2000
Page 22
Clean the Probe's Tip with ice machine cleaner and a clean, soft cloth.
Bearing Maintenance
NME954R & FME1204R
The top bearing in the breaker should be checked at least two times per year.
Check the breaker bearing by:
removing the ice chute cover
·
Chute Cover
unscrewing the ice sweep
·
Ice Sweep
unscrewing the auger stud
·
Auger Stud
Cap Screw
Inspect the bearing. There should be plenty of grease in sight. If grease is needed the bearing and breaker should be removed to check the action of the bearing. It should rotate smoothly.
To remove the breaker remove the lower ice chute then take out all four allen head cap screws and pull the breaker off the auger and evaporator.
·
removing the water shed
O
f
f
If the bearing only needs grease, inject grease into the bearing using Scotsman grease needle pn 02-3559-01 and Scotsman bearing grease cartridge, pn A36808-001. Be sure to inject grease evenly and thoroughly.
Needle
Breaker
Cover
·
unscrewing the breaker cover (left hand thread)
January 2000
Page 23
NME954R & FME1204R
Auger Maintenance
In some areas the water supply to the ice maker will have a great deal of minerals in it, and that will result in an evaporator and auger becoming coated with these minerals, requiring a more frequent removal than twice per year. If in doubt about the condition of the evaporator and auger, the auger can be removed so the parts can be inspected.
Note: Water filters can filter out suspended solids, but not dissolved solids. “Soft” water may not be the complete answer. Check with a water treatment specialist regarding water treatment
For more information on removal and replacement of these parts, see REMOVAL AND REPLACEMENT.
Moving parts hazard.
Moving parts can cause personal injury. Disconnect power before beginning to service components.
Allen
Screws
Breaker & Bearing &
Auger
Assembly
1. To remove the auger, remove the front and top panels.
2. Push back bail clamp holding ice chute cover to ice chute, and remove cover.
3. Unscrew and remove ice sweep.
4. Rremove ice chute from evaporator.
5. Remove 4 allen screws holding breaker to evaporator.
6. Pull up to remove auger.
After the auger has been removed, allow the auger to dry; if the auger is not bright and shiny, it must be cleaned.
Clean the auger and evaporator as required.
DO NOT HONE THE EVAPORATOR.
7. Replace the water seal.
8. Reverse to reassemble.
January 2000
Page 24
NME954R & FME1204R
SERVICE DIAGNOSIS: No Ice
Symptom Possible Cause Probable Correction
No ice is made, nothing operates Unit off due to no power. Restore power
Unit off due to master switch in Off position
Unit off due to low water level in reservoir
Unit off due to ice level sensors (photo-electric eyes) blocked
Unit off due to scale on water level sensor
Unit off due to high pressure control open
Auger motor hums but does not turn Auger can’t turn. Circuit board has not
Unit is shut down Circuit board has shut ice machine
Pump down pressure control open, very low suction pressure
Move master switch to ON
Check water supply, filter and float valve.
Check/clean ice level sensors
Clean water level sensor
Check for remote condenser fan motor failure or power interruption to the fan motor
yet shut unit down.
down due to high auger motor amp draw. Check for cause of high amp draw, including bearings, gear motor condition and scale on auger & evaporator.
Auger not turning due to: motor failure; auger relay failure on circuit board; or gears stripped. Check drive train.
Liquid line valve not opening due to coil failure or failure of compressor relay on circuit board
TXV restricted or not metering. Check bulb temperature.
Lack of refrigerant. Check for a leak.
No power to circuit board Check harness
Low or high pressure controls open
Circuit board gear motor relay will not close
Water level or ice level sensor failed Check / replace sensor
No ice, auger motor is turning Compressor contactor coil is open Check / replace contactor
Compressor will not start Check start capacitor
Circuit board relay will not close Check / replace board
Pump down pressure switch contacts do not close, liquid line valve open and suction pressure high
Check / replace board
Check start relay
Check compressor windings
Check pump down switch contacts
January 2000
Page 25
NME954R & FME1204R
SERVICE DIAGNOSIS: Low Capacity
Symptom Possible Cause Probable Correction
Unit makes ice, but very slowly High discharge pressure because of a
dirty condenser coil
Auger and evaporator are coated with mineral scale
Low refrigerant charge Locate leak. Recover refrigerant,
Water leak Ice storage bin drain restricted Clean out drain
Tubing cracked Replace tubing
Condensation on drain tubing Insulate tubing
Hose off Re-attach hose
Reservoir cover off Return cover to reservoir
Reservoir cracked Replace reservoir
Evaporator water seal leaks Check base of evaporator & drip pan.
Excessive ice meltage Bin drain clogged Clean out bin drain
Clean the condenser
Clean the water system
repair leak, replace dryer, evacuate and weigh in the nameplate charge.
If the seal leaks, shut off the wter, remove the auger, replace the water seal. Check gear motor for water infiltration.
Poor fit between bin door and door frame
Machine makes too much noise Evaporator coated internally with
minerals
Motor bearings dry Oil or replace motor
Adjust or replace
Clean with Scotsman Ice Machine Cleaner
January 2000
Page 26
CONTROL SYSTEM DIAGNOSTICS
NME954R & FME1204R
The control system consists of:
Control Board
·
Water Sensor
·
Ice Sensors
·
High Pressure Cut Out
·
Low Pressure Cut Out
·
If the unit is OFF, check the control board:
1. Is the Power OK light on? If not check power to the unit. If it has power, and the Power OK light is NOT on, check the high pressure and low pressure cut outs. If they are both closed, replace the board. If the Power OK light is ON, go to the next step.
2. Is the Water OK light on? If it is, go to the next step. If not, check the water level in the reservoir. If there is water in the reservoir, check that the water sensor is plugged in. To check the water sensor:
A. Unplug water sensor.
B. Pull water sensor from reservoir.
C. Place one ohmmeter lead on the sensor's plug and the other on the sensor's tip. The meter should show nearly zero resistance. If it reads infinite resistance, check the tip for corrosion. If it is clean and still reads open, replace the sensor.
seconds the Bin Full light on the board will go out. If master switch is ON, the unit should start.
4. High pressure cut out check.
Disconnect electrical power.
Pull the wires off the high pressure cut out.
Use an ohmmeter to determine if the switch is OPEN, If it is, check the discharge pressure. If the discharge pressure is less than 300 PSIG, replace the high pressure cut out.
If the high pressure cut out is open and the system has high discharge pressure, check for the cause.
5. Low pressure cut out check.
Disconnect electrical power.
Pull the wires off the low pressure cut out.
Use an ohmmeter to determine if the switch is OPEN, If it is, check the suction pressure. If the suction pressure is greater than 20 PSIG, replace the low pressure cut out.
If the low pressure cut out is open and the system has low suction pressure, check for the cause.
OR connect a copper wire to the wire where the water sensor plugs into and place the other end in the water. The water OK light should go ON. If it does not, replace the control board.
3. Ice sensor check. Is the Bin Full light Off? If it is OFF and the Service light is Off, and the unit is not running, replace the control board.
If it is OFF and the auger motor is running but the compressor is not, check the compressor contactor coil.
If it is on, the ice sensors may be blocked. Remove them and check for mineral scale. Scotsman's test box can also be used to determine if the ice sensors or board are defective.
Using the tester:
A. Disconnect the ice sensors at the connection by the ice chute. Connect the LED and PHOTO TRANS wires to the control board's wires.
B. With the On - Off (mode) switch in either position, move the Bin Full switch on the tester to Bin Full - the tester's light will blink and after a few seconds the bin full light on the control board will come on. If not, replace the board.
Move the Bin switch on the tester to Bin Empty. The light on the tester will go out, and after a few
January 2000
Page 27
NME954R & FME1204R
REMOVAL AND REPLACEMENT: Water Reservoir & Bin Controls
WATER RESERVOIR
1. Shut off the water supply to the ice maker.
2. Remove front panel and reservoir cover.
3. To remove float only, disconnect water inlet compression fitting at reservoir inlet.
4. Push in the tab behind the reservoir and pull the valve assembly up and out of the reservoir tank.
5. To remove reservoir, remove drain hose from reservoir.
6. Remove evaporator inlet hose from reservoir.
7. Remove mounting screws from reservoir bracket, and remove reservoir from ice maker.
8. Reverse to reassemble.
Float
Assembly
Water
Sensor
Slide Bin
Controls to
Remove
Ice Chute
Locking
Tabs
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 behind it are two plastic bin control mounts.
5. Slide each bin control to the left, and in the control box, disconnect the electrical leads connecting the bin control to the circuit board.
6. Reverse to reassemble, be certain that the bin controls are aligned so that the ice level sensors are visible (centered) through the holes in the ice chute.
January 2000
Page 28
NME954R & FME1204R
REMOVAL AND REPLACEMENT: Bearing and Breaker
Note: Removal of the auger, water seal, evaporator and gear motor must begin at the top of the assembly.
To Remove the Breaker Bearing Assembly:
Moving Parts Hazard. Disconnect electrical power before beginning.
1. Remove panels and disconnect electrical power.
2. Push back bail clamp and remove ice chute cover.
3. Unscrew and remove ice sweep.
4. Lift up and remove ice chute.
5. The breaker may be removed from the auger and evaporator without disturbing the auger.
a. Unscrew the breaker cover from breaker (left
hand threads)
b. Unscrew auger stud from top of auger.
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 the bearing and replace it an arbor press is needed.
b. Replace lower seals before installing new bearing in breaker.
Note: seals must be pressed in with a tool (such as 2” PCV coupling) pushing against the outer edge only, they will not install by hand.
Replace parts as required. Re-grease bearing with Scotsman part no. A36808-001 bearing grease. Replace top seal, and check the o-rings, replace if cut or torn.
7. Reverse to reassemble: specific tools and materials are required to install properly.
a. Add food grade grease such as Scotsman part number 19-0569-01 to the seal area before installing on the auger.
b. Check the seal to shaft areas for cuts, or rough spots: none are permitted.
c. Unscrew 4 allen head cap screws holding
breaker to evaporator.
Note: Flaker Components Shown, Nugget Similar, but Without Slotted Collar.
Step 5-a Step 5-b Step 5-c and Step 6
Ice
Sweep
Auger
Stud
Slotted
Collar
Allen
Screws
January 2000
Page 29
NME954R & FME1204R
REMOVAL AND REPLACEMENT: Auger
To Remove the Auger:
Turn off the water to the machine, and unclip the evaporator drain hose, pull it down and drain the evaporator into the bin or a container.
1. Remove the top panel.
Moving Parts Hazard.
Rotating parts can cause personal injury. Disconnect electrical power before beginning.
2. The auger and breaker/bearing may now be removed as an assembly.
a. Unscrew 4 allen head cap screws holding
Breaker Bearing
Assembly
breaker to evaporator.
Inspect the auger, the critical areas of the auger are:
a. The auger body. It should be clean and shining. Sometimes an auger will appear clean when wet, but after it is dry it will be seen to be stained. Scrub the auger with ice machine cleaner and hot water.
Ice machine cleaner is an acid. Handle it with extreme care, keep out of the reach of children.
b. The water seal area. Because the auger has been removed, the water seal will have to be replaced. Remove the water seal top half from the auger, and inspect the auger for minerals clean as required.
b. Lift up on breaker and remove auger from evaporator.
Note: If the auger is stuck, the breaker must be removed from the auger.
The breaker may be removed from the auger and evaporator without disturbing the auger.
a. Unscrew breaker cover from breaker (left hand threads)
b. Unscrew auger stud from top of auger.
c. Unscrew 4 allen head cap screws holding breaker to evaporator.
d. Lift up on breaker to remove from auger.
Thread
Into
Auger
Stop
Slide Hammer Puller
Removing Auger
Drive Slide Up
Against Stop To
Loosen Auger
If the auger is stuck:
Use a slide hammer type puller to pull on the auger at the threaded hole. The size of that hole is 5/8"-18.
January 2000
Page 30
NME954R & FME1204R
REMOVAL AND REPLACEMENT: Water Seal
To Remove the Water Seal:
(Assuming all steps to remove the auger have been performed.)
1. The gear motor/evaporator assembly will have to be pulled away from the machine (if not yet done).
2. Remove the 4 hex head cap screws holding the evaporator to the gear motor assembly. Lift the evaporator up and off of the gear motor.
3. Remove the snap ring or wire retainer from the grove under the water seal.
To Replace the Water Seal:
1. Lubricate the water seal with water, and push the water seal into the bottom of the evaporator slightly past the grove for the retaining ring.
2. Replace the retaining ring and pull the water seal down 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 sealant (such as 732 RTV or Scotsman part number 19-0529-01) on the area of the auger where the water seal is to be mounted.
5. Carefully push the water seal (rubber side against the auger shoulder and the silastic.)
Water Seal
Retaining Ring
REMOVAL OF THE
WATER SEAL
4. Pull or drive out the lower half of the water seal.
Place A Bead Of
Food Grade
Sealant Here
CAUTION
Do not get any sealant onto the face of the seal.
6. Allow the auger and seal to air dry until the silastic is dry on the surface.
7. If the original water seal was leaking, it would be a good idea to inspect the interior of the gear motor.
January 2000
Page 31
NME954R & FME1204R
REMOVAL AND REPLACEMENT: Evaporator
To Replace the Evaporator:
(Assuming all the steps for removal of the thrust bearing, breaker, auger, and water seal have been performed.)
1. Discharge the refrigerant from the ice maker.
2. Unsweat the refrigerant connections:
a) At the thermostatic expansion valve outlet.
CAUTION
Heat sink the TXV body when unsweating or resweating the adjacent tubing.
b) At the suction line at the joint about 3" from the evaporator.
3. Remove the evaporator.
4. Unsweat the drier from the liquid line.
5. After installing a new water seal in the new evaporator ( see “To Replace the Water Seal”) resweat the tubing connections.
6. Install an new drier in the liquid line.
7. Evacuate the system until dehydrated, 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”
To Reassemble the Evaporator and Auger
1. After the gear motor has been inspected, fasten the evaporator to the gear motor, be sure that the number of shims indicated on the gear case cover is in place between the gearcase cover and the drip pan gasket. Torque the bolts to 110 inch pounds.
2. Lower the auger into the evaporator barrel, slightly turning it to match up with the drive end. Do Not Drop Into the Evaporator.
3. Complete the reassembly by reversing the disassembly for the breaker & thrust bearing assembly.
January 2000
Page 32
NME954R & FME1204R
REMOVAL AND REPLACEMENT: Gear Motor Assembly
To Check the Motor:
Electrical Shock Hazard.
Disconnect electrical power before beginning.
1. Remove wires from terminals 1 and 2.
2. Use an ohmmeter to check for continuity and grounds. If there is continuity but the motor will not start, check the motor's start switch.
3. Remove the motor end bell or motor stator. With the ohmmeter wires attached to 1 and 2 move the centrifugal switch actuator up and down to simulate motor speed. If the ohmmeter does not show any change, or shows and open circuit, replace the switch or motor.
To Remove and Repair the Gear motor Assembly:
check the gears and bearings. They are likely to be fine if the oil is.
If there is evidence of water in the oil (rusty bearings and gears; the oil having a creamy white appearance; oil level too high) carefully inspect the bearings and gears. If in doubt about the condition of a part, replace it. The oil quantity is 14 fluid ounces, do not overfill.
Note: The gears and bearings are available only as pressed together sets.
D) After replacing parts as required, (if any) reassemble the gearcase. The two smaller gears and the oil should be in the lower case, the output gear will be with the cover. As you lower the cover onto the lower case, cover will have to be moved closer to the second gear after the output gear has cleared the second gear top bearing.
E) After the case is together, and the locating pins are secure in both ends, replace all cap screws.
4. Bench test the gear motor, check for oil leaks, noise, and amp draw.
(Assuming that the procedures through removal of the water seal have been performed.)
1. Remove the electrical wires from the gear drive motor.
2. Unscrew the 4 cap screws holding the gear motor to the unit.
3. Remove the gear motor from the ice maker.
To Inspect the gear motor.
A) Remove the cap screws holding the gear motor case halves together and pry the two cases apart.
B) To lift off the cover, lift up until you can feel internal contact, then pull the cover towards the output gear end, and then lift the cover (with drive motor attached) up and away from the gear motor case.
Note: The case cover output gear, bearings, and shaft are one pressed together assembly. Replace as a unit.
Water
Shed
Cover and
Output Gear
Assembly
Centrifugal
Switch
Rotor
Bearing
C) Inspect the oil, gears, and bearings. If the oil level and condition is acceptable, quickly
January 2000
Page 33
NME954R & FME1204R
Refrigeration Service
This ice machine uses R-404A refrigerant and polyolester oil. Do NOT use mineral oil in this refrigeration system.
R-404A is a “Near Azeotrope” so liquid charging
·
is required:
When the system is serviced, a special liquid
·
line drier is required. It is included with replacement compressors.
R-404A is not compatible with mineral oil, so
·
these ice machines use Polyolester oil. Polyolester oil absorbs water very easily. When one of these refrigeration systems is opened for service, it must be re-sealed as soon as possible (15 minutes maximum).
Special leak detection equipment is required to
·
locate small refrigerant leaks. Usually a leak detector capable of detecting a Halongenated refrigerant or HFC-134a will work. Check with the leak detector manufacturer if in doubt.
Access Valves: To use the access valves:
Remove the cap from the stem, use a 3/16"
·
allen wrench to check that the valve is CLOSED. The remove the core cap.
· Close the valve and replace the caps when the
job is finished. The valve must be closed and the caps must be on or the valve will leak.
Charging Procedures
·
Extra care must be taken when recharging this remote system. No liquid refrigerant may be placed in the system at the compressor. DO NOT use the access valves at the front of the unit for weighing in the charge. All liquid refrigerant must be weighed into the receiver through the front seated "king valve".
ALLEN
WRENCH
Torque Stem
to 6-8 ft. lb..
Front Seated
King Valve
Torque Cap to
8-12 ft. lb..
ACCESS
VALVE
Torque Cap to
7-12 ft. lb..
Receiver
Service Port
January 2000
Page 34
Charging
Cylinder
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