STERO SU-L User manual

STERO, a division of Illinois Tool Works, Inc. 1758 Corporate Circle Petaluma, CA 94954
Phone: [phone] Fax: [phone] Website: Stero.com
ST50406 (01/16)
STERO
Undercounter Undercounter
Dishwasher Glasswasher
MODELS: MODELS:
SU-L ML-130274 SG-42 ML-130259
SU-H ML-130273 SG-40 ML-130289
INSTRUCTION
MANUAL

2| STERO UNDERCOUNTER DISHWASHER & GLASSWASHER
TABLE OF CONTENTS
GENERAL
SU Dishwashers ........................................................................3
SG Glasswashers .......................................................................4
START-UP CHECKLIST ................................................................5
INSTALLATION ........................................................................6
Unpacking ............................................................................6
Location..............................................................................6
Leveling ..............................................................................6
Water Requirements .................................................................. 6-7
Plumbing Connections ..................................................................7
Electrical Connection ...................................................................8
Electrical Data .........................................................................8
Connection Method ..................................................................8-9
Detergent and Rinse Aid.................................................................9
Chemical Sanitizer (SU-L & SG Models) ....................................................10
Checking Sanitizer Concentration ........................................................11
Priming Chemical Pumps................................................................11
Installation Diagrams
SU Dishwashers ....................................................................12
SG Glasswashers .................................................................13-14
PARAMETERS MENU TABLE ........................................................15
OPERATION ..........................................................................16
Before First Use .......................................................................16
Controls .............................................................................16
Operating the Stero Dishwasher & Glasswasher .............................................17
Diagnostic/Error Messages ..............................................................18
Wash/Rinse Cycle Times.................................................................19
Preparation ..........................................................................19
CLEANING ............................................................................20
Do's and Don'ts for Your New Stero Dishwasher ............................................20
MAINTENANCE ......................................................................21
Deliming ............................................................................21
Lubrication ..........................................................................21
TROUBLESHOOTING .............................................................. 22-23
©STERO 2014

STERO UNDERCOUNTER DISHWASHER & GLASSWASHER | 3
GENERAL
Installation,
Operation
and Care of
SU SERIES
DISHWASHERS
SAVE THESE INSTRUCTIONS
The Stero SU dishwashers are fully automatic, front-loading dishwashing machines. The machines are capable
of doing 31-33 racks per hour.
All SU Series dishwashers shut down automatically 4 hours after last use to conserve energy.
All SU-H Series dishwashers include rinse assurance tehnology to insure proper hot water temperature during
rinse.
Standard equipment includes electronic controls, drain pump, rinse pump, chemical pumps, fill hose, and drain
hose.
MODEL DESCRIPTION
SU-L Fresh water rinse; low-temperature, chemical-sanitizing models for use with 6% sodium hypochlo-
rite solution (bleach) as the sanitizing agent*. Note: If 8.40% bleach is to be used, contact your local
service provider or your chemical supplier to change the sanitizer pump settings. (Charges may apply)
SU-H Fresh water rinse with a built-in 70°F rise booster heater. This allows an incoming water temperature
of 110°F.
*Sanitizing agent must be used in accordance with the EPA-registered label use instructions.

4| STERO UNDERCOUNTER DISHWASHER & GLASSWASHER
The Stero SG glasswasher is fully automatic and front-loading. The machine is capable of doing 34 racks per
hour.
All SG glasswashers shut down automatically 4 hours after last use to conserve energy.
Standard equipment includes electronic controls, drain pump, rinse pump, chemical pumps, fill hose, and drain
hose.
MODEL DESCRIPTION
SG Fresh water rinse; low-temperature, chemical-sanitizing models for use with 6% sodium hypochlo-
rite solution (bleach) as the sanitizing agent*. Note: If 8.40% bleach is to be used, contact your
local service provider or your chemical supplier to change the sanitizer pump settings. (Charges may
apply)
*Sanitizing agent must be used in accordance with the EPA-registered label use instructions.
GENERAL
Installation,
Operation
and Care of
SG
GLASSWASHER
SAVE THESE INSTRUCTIONS

STERO UNDERCOUNTER DISHWASHER & GLASSWASHER | 5
START-UP CHECKLIST
BEFORE POWER IS APPLIED
____ 1. Check all utility service connections for tightness.
____ 2. Check for any loose hardware, level machine, check for proper form fit of side panels and top
control lid.
____ 3. Check door closing operation.
____ 4. Check free rotation of wash/rinse arms, remove any inside packing material.
____ 5. Check all wash strainers in place (dishracks slide in freely).
____ 6. Check proper routing of all chemical tubing out rear of machine to bottle (red – detergent, blue – rinse
aid, white – sanitizer)
AFTER POWER IS APPLIED AND WATER TURNED ON
____ 1. Verify correct supply voltage and phase to machine. Confirm with data plate.
____ 2. Turn machine on, start warming up/fill cycle.
____ 3. Wait for “Ready” status for both holding/booster tank and sump.
____ 4. Check for leaks.
____ 5. Verify proper water levels.
RUN CYCLE(S) AND CHECK THE FOLLOWING
____ 1. Check for proper operation of keypad and display illumination.
____ 2. Check operation of door interlock switch, and good seal of door gasket.
____ 3. Check for proper pump motor operation and check for leaks.
____ 4. Verify proper water flow out drain, during drain portion of cycle.
____ 5. Verify proper operation of rinse pump (proper flow of water out final rinse arms).
____ 6. Verify final rinse temperature.
____ 7. Test bleach concentration, while running bleach rinse cycle (gold only) (50-100 ppm).
REINSTALL ANY PANELS REMOVED

6| STERO UNDERCOUNTER DISHWASHER & GLASSWASHER
UNPACKING
Immediately after unpacking the dishwasher, check for possible shipping damage. If this machine is found to
be damaged, save packaging material and contact the carrier within 15 days of delivery.
LOCATION
Prior to installation, verify that the electrical supply agrees with the specifications on the machine data plate,
which is located on the top of the door.
Steam generated from normal operation may escape from the door. Wood, laminates, veneers, etc. are
unsuitable materials for use in areas exposed to dishwasher steam and detergents. Stainless steel or other
moisture-resistant shields are recommended for surfaces adjacent to dishmachine sides and top.
LEVELING
The machine must be level to operate properly. Place the dishwasher in its operating location. Level the machine
before any connections are made. Using a carpenter's level placed diagonally on the rack tracks, level the
machine front to back and side to side by threading the adjustable feet in or out. After leveling the machine,
cover the exposed threads of the adjustable feet with black rubber tubing supplied. (See separate instructions
furnished with machine.)
WATER REQUIREMENTS
Proper water quality can improve ware washing performance by reducing spotting, enhancing effectiveness of
labor and extending equipment life. Water conditions vary from one location to another. The recommended
proper water treatment for effective and efficient use of this equipment will also vary depending on the local
water conditions. Ask your municipal water supplier for details about your local water conditions prior to
installation.
Recommended water hardness is 3 grains of hardness per gallon or less. Higher hardness may cause excessive
formation of lime scale. Water hardness above 3 grains per gallon requires water treatment. Water treatment
has been shown to reduce costs associated with machine cleaning, reduce deliming of the dishwasher, and
reduce detergent usage in the dishwasher.
High iron levels in the water supply can cause staining and may require an iron filter. High chloride
levels in the water supply can cause pitting and may require a chloride removal system. Contact your local
water treatment professional for proper water treatment.
Sediment may require a particulate filter. Dissolved solids may require water treatment such as a water soft-
ener, reverse osmosis system, etc. Contact your local water treatment professional for proper water treatment.
If an inspection of the dishwasher or booster heater reveals lime buildup after the equipment has been in
service, water treatment is recommended. If a water softener is already in place, ensure there is a sufficient
level of salt.
A water hammer arrestor (meeting ASSE-1010 Standard or equivalent) should be installed (supplied by others)
in the common water supply line at the service connection.
INSTALLATION

STERO UNDERCOUNTER DISHWASHER & GLASSWASHER | 7
The plumber connecting this machine is responsible for making certain that water lines are THOROUGHLY
FLUSHED OUT BEFORE connecting to the dishwasher. This “flush-out” is necessary to remove all foreign mat-
ter, such as chips (resulting from cutting or threading of pipes) pipe joint compound from the lines; or, if
soldered fittings are used, bits of solder or cuttings from the tubing. Debris, if not removed, may lodge in the
dishwasher’s plumbing components and render them inoperative. Manual valves or solenoid valves fouled by
foreign matter and any expenses resulting from this fouling are NOT the responsibility of the manufacturer
and associated repair costs are not covered under warranty.
Water supply requirements are as follows:
Model Description
SU-L 120°F Minimum
SU-H 110°F Minimum
SG 120°F Minimum
Required flowing water pressure to the dishmachine is 15-65 PSIG. If pressures higher than 65 PSIG are present,
a pressure regulating valve must be installed in the water line to the dishmachine (by others). If flowing pres-
sure is less than 15 psi, improper machine operation may result. The dishmachines are equipped with a pumped
rinse system; therefore, a water pressure gauge is not required and is not supplied with the machine.
The water pressure regulator must have a relief bypass. Failure to use the proper type of pressure
regulator may result in damage to the unit.
A manual shutoff valve (not supplied) should be installed upstream of the fill hose to accommodate servicing
the machine.
It is recommended that a line strainer (not supplied) be installed in the supply line between the manual shutoff
valve (not supplied) and the connection point on the machine. Make plumbing connections with
1
⁄ 2 " minimum
copper piping OD (
3
⁄ 4 " recommended), with a
3
⁄ 4 " male garden hose fitting (not supplied). See installation
diagram,s, pages 12-14.
PLUMBING CONNECTIONS
Plumbing connections must comply with applicable sanitary, safety, and plumbing
codes.
Drain
A drain hose,
5
⁄ 8 " inside diameter and 6' long, is provided. This should be securely plumbed into a drain. Use
care not to kink hose. See installation diagrams, pages 12-14. Drain must have a minimum flow capacity of
5 gallons per minute.
INSTALLATION (continued)

8| STERO UNDERCOUNTER DISHWASHER & GLASSWASHER
ELECTRICAL CONNECTION
Electrical and grounding connections must comply with the applicable portions of
the National Electrical Code and/or other local electrical codes.
Disconnect the electrical power to the machine and follow lockout/tagout proce-
dures.
ELECTRICAL DATA
Complied in accordance with the National Electrical Code NFPA-70, latest addition.
For supply connections, use copper wire only rated at 90°C minimum.
Model Volts/Hertz/Phase
Minimum Supply
Circuit Conductor
Ampacity
Maximum
Protective Device
Ampacity
SU-L 120/60/1 20 20
SU-H 120/208-240
(3W)/60/1* 40 40
SG 120/60/1 20 20
* The (3W) systems require three power wires that include a current carrying neutral. An additional fourth
wire must be provided for machine ground.
Refer to the data plate on the door handle of the machine and the electrical label on the back side of the
lower front panel for proper selection.
CONNECTION METHOD
1. Remove the lower front panel by removing the two screws at the bottom of the panel (Figure 1).
2. Open door of dishwasher and remove the two left screws and the top right screw (Figure 2). Pull top of
unit forward approximately 1" and remove the left side panel.
INSTALLATION (continued)
Figure 1 Figure 2
REMOVE TWO SCREWS
REMOVE THREE SCREWS

STERO UNDERCOUNTER DISHWASHER & GLASSWASHER | 9
KNOCKOUT
INSTALLATION (continued)
3. A hole for 1" trade size conduit is supplied at the lower right in the back of the machine (Figure 3). If
necessary due to space requirements, remove the knockout and use a 45° fitting.
4. Install 1" trade size conduit and fitting. Leave at least four feet of electrical line between wall connection
and machine. This allows machine to be pulled away from the wall for cleaning and/or servicing.
5. Feed wires thru base of unit to front of unit. At least 24" and not more than 28" of the required wire
size must extend from the end of the conduit fitting.
6. Make electrical connections according to wiring diagram supplied with the machine and secure wires
to the machine service connection. Keep excess wire in the base of the unit to a minimum.
7. Replace the left side panel, top of unit, and lower front panel. Re-install the three screws located behind
the door and the two screws at the bottom of the front panel.
Figure 3

10 | STERO UNDERCOUNTER DISHWASHER & GLASSWASHER
DETERGENT AND RINSE AID
Use only commercial-grade detergents recommended by your chemical professional. Do not use detergents
formulated for residential dishwashers.
SU UNDERCOUNTER ONLY:
The detergent and rinse aid pump “ON” times are factory-set. If adjustments are required, contact your local
service provider or your chemical supplier.
Place the detergent and rinse aid containers (which are obtained from an independent supplier) in a location
where the delivery tubes will reach them.
Remove the detergent bottle cap and put the red delivery tube in the detergent container.
Remove the rinse aid bottle cap and place the blue delivery tube in the rinse aid container.
Be sure to push the delivery tube standpipes completely to the bottom of each container. Check to make sure
there are no obstructions or kinks in the delivery tubes.
SG GLASSWASHER ONLY:
Place the detergent and rinse aid containers (which are obtained from an independent supplier) under the
glasswasher (or nearby for shorter version).
Remove the detergent bottle cap and put the red delivery tube in the detergent container by snapping the
bottle connector onto the container.
Remove the rinse aid bottle cap and place the blue delivery tube in the rinse aid container by snapping the
bottle connector onto the container.
Be sure to push the delivery tubes completely to the bottom of each container. Check to make sure there are
no obstructions or kinks in the delivery tubes.
CHEMICAL SANITIZER
Items such as pewter, aluminum and silver will be attacked by sodium hypochlorite (bleach).
Therefore, chemical-sanitizing dishwashers should not be used to wash such items.
The chemical sanitizer pump is factory-set for use with 6% sodium hypochlorite solution.
On SU-L & SG models, place a 1-gallon bottle of 6% or 8.40% sodium hypochlorite solution (bleach) in a suit-
able location no higher than 10 inches off the floor. Do not pre-mix sanitizing solution with water or any other
liquid.
Never premix a wetting agent with the sanitizing solution. Mixing may cause
hazardous gas to form.
Remove the sanitizer bottle cap and place the white delivery tube in the sanitizer container. Be sure to push
the delivery tube standpipe completely to the bottom of the container. Check to make sure there are no
obstructions or kinks in the delivery tube.
Frequently check your sanitizer bottle to make sure there is a sufficient chemical supply.
INSTALLATION (continued)

STERO UNDERCOUNTER DISHWASHER & GLASSWASHER | 11
CHECKING SANITIZER CONCENTRATION
Verify there is sufficient chemical supply in the sanitizer bottle and that the delivery tube standpipe is inserted
completely to the bottom of the chemical container. Place a glass rack, with glasses, in the machine.
Press the WASH key to run a cycle. At the end of the cycle, open the door.
Follow the directions precisely that are on the litmus paper vial and test the water on the surface of the bottom
of the glasses. Concentration should be 50 p.p.m. minimum to 100 p.p.m. maximum.
If reading is incorrect, contact your chemical provider for adjustments.
PRIMING CHEMICAL PUMPS
When a chemical becomes empty, the priming operation starts automatically the next time the machine is
turned on or a wash cycle is started. Note that the initial prime time for all pumps (Detergent, Rinse Agent,
and Sanitizer) is 60 seconds. If the chemical is not sensed within 60 seconds, the add chemical indicator will
flash. After the chemical is sensed, the indicator in the display turns off; and the pump continues to prime for
10 seconds to allow the chemicals to reach the machine. If all chemicals are empty, the sanitizer will prime first
followed by detergent. Only one chemical pump will run at a time.
If chemicals are not sensed after three consecutive priming operations, the add chemical indicator will flash
and priming is cancelled. The next time a wash cycle is started, the add chemical indicator will continue to flash.
Verify that the chemical bottles are not empty and that the delivery tube standpipes are inserted completely
to the bottom of the containers.
The priming operation can be reset by turning the dishwasher off, then back on.
If the chemical bottles are not empty and the delivery tube standpipes are inserted correctly, then the chemical
sensor or pumps may have malfunctioned; contact your local chemical provider.
INSTALLATION (continued)

12 | STERO UNDERCOUNTER DISHWASHER & GLASSWASHER
FLOOR LINE
E1
P2
3
13/16"
22 5/16"
CHEMICAL BOTTLES
MAY BE LOCATED ON
EITHER SIDE OF MACHINE
32 3/4"
23 15/16"
RECOMMENDED WATER
SERVICE ROUGH-IN
1/2" TRADE SIZE
PIPE MIN. W/SHUTOFF
VALVE, LINE STRAINER
& 3/4" MALE GARDEN
HOSE FITTING (BY
CUSTOMER).
RECOMMENDED
17" OR LESS
1-1/2" TRADE SIZE
PIPE MIN. REDUCED
DOWN TO 3/4" FPT
CONNECTION (BY
CUSTOMER)
ADDITIONAL CLEARANCE REQUIRED TO
SLIDE UNIT FORWARD FOR SERVICE ONLY
TRIM STRIP
(OPTIONAL)
CHLORINE
SANITIZER
(SU-L ONLY) 32-3/4"
DETERGENT
&
RINSE-AID
40"
SERVICE
CLEARANCE
MIN
21"
25-9/16"
43-1/2"
17" MAX.
LOADING
HEIGHT
WALL
P2
E1 P2 P1
9"
MIN.
CHLORINE
SANITIZER
(SU-L ONL
Y)
OVERALL DIMENSIONS: 32-3/4"H x 23-15/16"W x 25-9/16"D
SHIPPING WEIGHTS
MODEL NET
WEIGHT DOMESTIC
SHIPPING WEIGHT
SU-H 150 lbs. 170 lbs.
SU-L 150 lbs. 170 lbs.
MODEL VOLTS/HERTZ/PHASE RATED
AMPS
MIN SUPPLY
CKT CONDUCTOR
AMPACITY
MAX
PROTECTIVE
DEVICE
SU-H 120/208-240(3W)/60/1* 30.5 40 40
SU-L 120/60/1 15.4 20 20
NOTE: FOR SUPPLY CONNECTIONS, USE COPPER WIRE ONLY RATED AT 90°C MINIMUM
ACCESSORY CORD KIT AVAILABLE FOR ALL MODELS.
* THIS SYSTEM REQUIRES THREE POWER WIRES WHICH INCLUDES A CURRENT CARRYING NEUTRAL, AN
ADDITIONAL FOURTH WIRE MUST BE PROVIDED FOR A MACHINE GROUND.
Do not premix other chemicals and sodium hypochlorite
(liquid bleach).
Mixing may cause hazardous gas to form (SU-L only).
Required flowing water pressure to the
dishmachine is 15-65 PSIG. If pressures higher
than 65 PSIG are present, a pressure regulating
valve must be installed in the water line to the
dishmachine (by others).
Pressure gauge not required on pumped rinse
machines.
Important: Chemical containers should be placed
no higher than 10" above floor.
If chemical containers are to be placed in cabinet
adjacent to machine, a 1/2" dia. hole is required
in the cabinet to run chemical supply line.
Use only 6% or 8.4% sodium hypochlorite (liquid
bleach) as sanitizing chemical to insure proper
operation of dishmachine (SU-L only).
CAUTION: CERTAIN MATERIALS, INCLUDING SILVER, ALUMINUM AND
PEWTER ARE ATTACKED BY SODIUM HYPOCHLORITE (LIQUID BLEACH) IN
THE CHEMICAL SANITIZING DISHWASHER MODE OF OPERATION. WATER
HARDNESS MUST BE CONTROLLED TO 4-6 GRAINS FOR BEST RESULTS.
Electrical and grounding connections must comply with the
applicable portions of the National Electrical Code and/or other
local electrical codes.
Plumbing connections must comply with applicable sanitary,
safety and plumbing codes. Drain and fill line configurations
vary, some methods are shown on this drawing.
CONNECTION INFORMATION
(AFF = ABOVE FINISHED FLOOR)
LEGEND
E1 ELECTRICAL CONNECTION: 1-3/8" DIA. HOLE FOR 1" TRADE SIZE CONDUIT;
4-5/8" AFF
P1 SINGLE FILL AND RINSE CONNECTION: 3/4" FEMALE GARDEN HOSE FITTING
ON 6' LONG HOSE SUPPLIED WITH MACHINE;
P2 DRAIN CONNECTION: 5/8" BARB FITTING WITH 6' LONG HOSE SUPPLIED WITH
MACHINE.
NOTES:
1. All vertical machine dimensions taken from floor may be increased by 1".
2. Moist air escapes from the door. Use only moisture resistant materials
adjacent to dishmachine sides and top.
3. A vent hood is not recommended above the undercounter dishmachine
since it does not produce excessive vapors.
PLUMBING NOTES:
1. Water hammer arrestor (meeting ASSE-1010 Standard or equivalent)
to be supplied (by others) in common water supply line at service
connection.
2. Recommended water hardness to be 3 grains or less for best results.
3. If drain hose is looped above a sink, the loop must not exceed 38" AFF.
INSTALLATION (continued)
SU UNDERCOUNTER DISHWASHER INSTALLATION DIAGRAM

STERO UNDERCOUNTER DISHWASHER & GLASSWASHER | 13
INSTALLATION (continued)
SG40 UNDERCOUNTER GLASSWASHER INSTALLATION DIAGRAM
Required flowing water pressure to the dishmachine is
15-65 PSIG. If pressures higher than 65 PSIG are present,
a pressure regulating valve must be installed in the
water line to the dishmachine (by others).
Pressure gauge not required on pumped rinse machines.
Important: The chemical containers should be placed no
higher than 24" above floor.
If chemical containers are to be placed in cabinet
adjacent to machine, a 1/2" dia. hole is required in the
cabinet to run chemical supply line.
Use only 6% or 8.4% sodium hypochlorite (liquid bleach)
as sanitizing chemical to insure proper operation of
dishmachine.
Certain materials, including silver plate, aluminum and
pewter are attacked by sodium hypochlorite (liquid
bleach). See instructional manual.
Electrical and grounding connections must
comply with the applicable portions of the
National Electrical Code and/or other local
electrical codes.
Plumbing connections must comply with
applicable sanitary, safety and plumbing codes.
Drain and fill line configurations vary, some
methods are shown on this drawing.
CONNECTION INFORMATION
(AFF = ABOVE FINISHED FLOOR)
LEGEND
E1 ELECTRICAL CONNECTION: 1-3/8" DIA. HOLE FOR
1" TRADE SIZE CONDUIT; 15-5/16" AFF
P1 SINGLE FILL AND RINSE CONNECTION: 3/4"
FEMALE GARDEN HOSE FITTING ON 6' LONG HOSE
SUPPLIED WITH MACHINE; 120°F WATER MIN.
FOR SG, 140°F RECOMMENDED.
P2 DRAIN CONNECTION: 5/8" BARB FITTING WITH
6' LONG HOSE SUPPLIED WITH MACHINE.
NOTES:
1. All vertical machine dimensions taken from
floor may be increased by .875" or decreased
by .375".
2. Moist air escapes from the door.
Use only moisture resistant materials
adjacent to dishmachine sides and top.
3. A vent hood is not recommended above the
undercounter dishmachine since it does not
produce excessive vapors.
PLUMBING NOTES:
1. Water hammer arrestor (meeting ASSE-1010
Standard or equivalent) to be supplied (by
others) in common water supply line at
service connection.
2. Recommended water hardness to be 3 grains
or less for best results.
3. If drain hose is looped above a sink, the loop
must not exceed 51" AFF.
Do not premix other chemicals and sodium
hypochlorite (liquid bleach).
Mixing may cause hazardous gas to form.
MODELS:
SG 40"
00-950420
REV C
FLOOR LINE
21 11/16"
23 15/16"
RECOMMENDED
31" OR LESS
1-1/2" TRADE SIZE
PIPE MIN. REDUCED
DOWN TO 3/4" FPT
CONNECTION (BY
CUSTOMER)
RECOMMENDED WATER SERVICE
ROUGH-IN 1/2" TRADE SIZE PIPE
MIN. W/SHUTOFF VALVE, LINE
STRAINER & 3/4" MALE GARDEN
HOSE FITTING (BY CUSTOMER).
E1 P2 3
27 3/4"
21 11/16"
1 3/8"
39 9/16"
26 11/16"
12" MAX
LOADING
HEIGHT
21 13/16"
38 7/8"
WALL
P2
E1 P2 P1
9"
MI
N
E1 DH
ADDITIONAL CLEARANCE REQUIRED TO
SLIDE UNIT FORWARD FOR SERVICE ONLY
DETERGENT
&
RINSE-AI
D
CHLORINE
SANITIZER
45 7/8"
SERVICE
CLEARANC
E
MIN
11 1/8"
38 7/8"

14 | STERO UNDERCOUNTER DISHWASHER & GLASSWASHER
INSTALLATION (continued)
Required flowing water pressure to the dishmachine is
15-65 PSIG. If pressures higher than 65 PSIG are present,
a pressure regulating valve must be installed in the
water line to the dishmachine (by others).
Pressure gauge not required on pumped rinse machines.
Important: The chemical containers should be placed no
higher than 24" above floor.
If chemical containers are to be placed in cabinet
adjacent to machine, a 1/2" dia. hole is required in the
cabinet to run chemical supply line.
Use only 6% or 8.4% sodium hypochlorite (liquid bleach)
as sanitizing chemical to insure proper operation of
dishmachine.
Certain materials, including silver plate, aluminum and
pewter are attacked by sodium hypochlorite (liquid
bleach). See instructional manual.
Electrical and grounding connections must
comply with the applicable portions of the
National Electrical Code and/or other local
electrical codes.
Plumbing connections must comply with
applicable sanitary, safety and plumbing codes.
Drain and fill line configurations vary, some
methods are shown on this drawing.
CONNECTION INFORMATION
(AFF = ABOVE FINISHED FLOOR)
LEGEND
E1 ELECTRICAL CONNECTION: 1-3/8" DIA. HOLE FOR
1" TRADE SIZE CONDUIT; 18-1/8" AFF
P1 SINGLE FILL AND RINSE CONNECTION: 3/4"
FEMALE GARDEN HOSE FITTING ON 6' LONG HOSE
SUPPLIED WITH MACHINE; 120°F WATER MIN.
FOR SG, 140°F RECOMMENDED.
P2 DRAIN CONNECTION: 5/8" BARB FITTING WITH
6' LONG HOSE SUPPLIED WITH MACHINE.
NOTES:
1. All vertical machine dimensions taken from
floor may be increased by .875" or decreased
by .375".
2. Moist air escapes from the door.
Use only moisture resistant materials
adjacent to dishmachine sides and top.
3. A vent hood is not recommended above the
undercounter dishmachine since it does not
produce excessive vapors.
PLUMBING NOTES:
1. Water hammer arrestor (meeting
ASSE-1010 Standard or equivalent) to be
supplied (by others) in common water supply
line at service connection.
2. Recommended water hardness to be 3 grains
or less for best results.
3. If drain hose is looped above a sink, the loop
must not exceed 51" AFF.
Do not premix other chemicals and sodium
hypochlorite (liquid bleach).
Mixing may cause hazardous gas to form.
MODELS:
SG 42"
00-950420
REV C
FLOOR LINE
RECOMMENDED
31" OR LESS
RECOMMENDED WATER SERVICE
ROUGH-IN 1/2" TRADE SIZE PIPE
MIN. W/SHUTOFF VALVE, LINE
STRAINER & 3/4" MALE GARDEN
HOSE FITTING (BY CUSTOMER).
DETERGENT
,
RINSE-AID,
CHLORINE
SANITIZE
R
BOTTLES MA
Y
BE LOCA
TED
UNDER THE
MACHINE
E1 P2 3
1-1/2" TRADE SIZE
PIPE MIN. REDUCED
DOWN TO 3/4" FPT
CONNECTION (BY
CUSTOMER)
23 15/16"
21 11/16"
P2
E1 P2 P1
WALL
13 15/16"
42 1/8"
48 11/16"
SERVICE
CLEARANC
E
MIN
ADDITIONAL CLEARANCE REQUIRED TO
SLIDE UNIT FORWARD FOR SERVICE ONLY
SG42 UNDERCOUNTER GLASSWASHER INSTALLATION DIAGRAM
21 11/16"
1 3/8"
26 11/16"
39 9/16"
41 11/16"
24 1/2"
27 3/4"
12" MAX
LOADING
HEIGHT

STERO UNDERCOUNTER DISHWASHER & GLASSWASHER | 15
Parameter
Name Description Possible Values
Default
Value
Detergent
Pump Enables or disables the detergent pump. Disabled or Enabled Enabled
Rinse Aid
Pump Enables or disables the rinse aid pump. Disabled or Enabled Enabled
Wash Cycle Sets the cycle duration. Light, Normal,
or Heavy Normal
Low Temp
Alarms
(SU-H
Model Only)
Enables or disables a visual alert on the display that indi-
cates that the Final Rinse water temperature is below the
required minimum of 180°F (82°C). When enabled, a mes-
sage will display notifying the user of this condition after
three consecutive cycles do not reach the required final rinse
temperature. However, machine operation will not change
and ware will continue to wash as expected. After the tem-
perature increases past the minimum, the message stops.
When disabled, there will be no extra message indicating a
low temperature event; however, the temperature display
will still show the current Final Rinse water temperature.
Disabled or
Enabled Disabled
Delime Enables or disables the alert to delime option. Disabled or
Enabled Enabled
Temperature
Units Sets the display units to either Fahrenheit or Celcius. Fahrenheit or Celsius Fahrenheit
Add
Chemical
Alert
Enables or disables an audible alert if chemical is not being
detected.
Disabled,
Visual, or
Audio and
Visual
Audio and
Visual
End Cycle
Audio Alert Enables or disables an audible alert at the end of a cycle. Disabled or Enabled Disabled
Language Sets the language on the display to either English or French.
English (US) or
French
(Canada)
English (US)
Exit Menu Press ENT to exit the Parameters Menu and return to the
Manager Menu. Any settings that were changed are saved.
PARAMETERS MENU TABLE

16 | STERO UNDERCOUNTER DISHWASHER & GLASSWASHER
OPERATION
Items such as pewter, aluminum and silver will be attacked by sodium hypochlorite (bleach).
Therefore, chemical-sanitizing dishwashers should not be used to wash such items.
If your dishwasher is a chemical-sanitizing model, frequently check the sanitizer bottle to make sure there is a
sufficient chemical supply.
BEFORE FIRST USE
This machine must be cleaned after installation and before being put into operation. (See Cleaning.)
CONTROLS
Figure 4

STERO UNDERCOUNTER DISHWASHER & GLASSWASHER | 17
OPERATING THE STERO DISHWASHER & GLASSWASHER
Do This Display Shows Remarks
Press ON. Model number. Dishwasher performs self-check. This
takes 5 seconds.
FILL and fill icon lit; sump temperature
displayed when machine is filling.
WARMING UP and warming up icon
are displayed when booster is pre-
heating. This preheat could take up to
15 minutes.
Dishwasher fills with water. When
filled, pump turns on for 10 seconds.
If door is opened during fill cycle, fill
will stop. After door is closed, the pro-
cess continues where it stopped.
During fill, sump temperature is
displayed.
When filled, machine will maintain an
idle state. Heat is maintained in both
sump and/or booster.
Open door; slide rack of dishes
into dishwasher. Close door.
READY lit and sump temperature
displayed.
Detergent will be added automatically
during wash cycle.
Rinse Aid and Sanitizer will be added
automatically during rinse cycle.
(NOTE: Sanitizer only used on SU-L &
SG models.)
Press WASH. WASH and wash icon lit; sump tem-
perature displayed during wash cycle.
RINSE and rinse icon lit; rinse tem-
perature displayed during rinse cycle.
Machine initiates a wash and rinse
cycle.
If door is opened during wash, rinse,
or drain cycle, cycle will continue at
point where door was opened upon
closing door.
If POWER is pressed during cycle,
machine will drain and shut down.
When cycle is complete, reload
machine for next wash/rinse
cycle; or, if not in use, machine
will maintain idle mode.
READY lit and sump temperature
displayed.
Machine will drain and shut down if
the four hour idle shutdown time is
reached.
At the end of the day, press
POWER.
DRAIN and SHUTDOWN IN PROGRESS
are displayed; then the display shuts
down.
When POWER key is pressed, machine
will drain and shut down.
OPERATION (continued)

18 | STERO UNDERCOUNTER DISHWASHER & GLASSWASHER
DIAGNOSTIC/ERROR MESSAGES
Error Display Description
Door Open Door Open Displayed when the door of the machine is
opened.
Low Rinse
Temperature LOW RINSE TEMP
After two consecutive low temperatures,
if problem occurs on the third consecutive
cycle, the error will display. The machine
will continue to run cycles.
Low Rinse
Temperature
(10 In A Row)
LOW RINSE TEMP
Check Water Input
If the Low Rinse Temperature error occurs
for 10 consecutive cycles, the error will
change. The machine will continue to run
cycles.
Wash
Thermistor
Error
WASH TEMP SENSOR
Service Required
(Service Phone Number)
OPEN or SHORT
Error displayed if wash temperature probe
is out of range. The machine will continue
to run cycles.
Booster
Thermistor Error
BOOSTER TEMP SENSOR
Service Required
(Service Phone Number)
OPEN or SHORT
Error displayed if booster temperature
probe is out of range. The machine will
continue to run cycles. (SU-H model only.)
Final Rinse
Thermistor
Error
RINSE TEMP SENSOR
Service Required
(Service Phone Number)
OPEN or SHORT
Error displayed if final rinse temperature
probe is out of range. The machine will
continue to run cycles.
Low Water In
Booster (Time
Out Within
Any Cycle)
FILL ERROR
Service Required
(Service Phone Number)
Error displayed if the unit times out before
the unit is completely filled. The machine
will not operate and will only allow power
down.
Drain Error
DRAIN ERROR
Service Required
(Service Phone Number)
Error displayed if the water level in the
unit will not come up. The machine will not
operate and will only allow power down.
Sump Level Error
SUMP LEVEL SENSOR
Service Required
(Service Phone Number)
OPEN or SHORT
Error displayed if sump pressure switch is
out of range. The machine will not operate
and will only allow power down.
Booster Level
Error
BOOSTER LEVEL SENSOR
Service Required
(Service Phone Number)
OPEN or SHORT
Error displayed if booster pressure switch is
out of range. The machine will not operate
and will only allow power down.
OPERATION (continued)

STERO UNDERCOUNTER DISHWASHER & GLASSWASHER | 19
OPERATION (continued)
WASH/RINSE CYCLE TIMES
SU-L SU-H SG
Wash 85 Seconds Wash 85 Seconds* Wash 85 Seconds
Drain 12 Seconds Drain/Dwell 20 Seconds Max Drain 10 Seconds
Rinse 12 Seconds Rinse 11 Seconds Rinse 10 Seconds
* Maximum wash time may vary, depending on operation voltage and incoming water temperature for 70°F rise on SU-H machines.
PREPARATION
Make sure the coarse (Figure 5) and fine (Figure 6) strainers are in place and free of debris. Ensure that the
coarse strainer is installed with the handle towards the front of the machine. Check both wash arms and rinse
arms to make sure they spin freely and are not clogged.
Figure 5 Figure 6
Dishes must be scraped and/or rinsed to remove food particles and other debris. Never use steel wool on ware
to be loaded into the dishwasher. Place dishes in a rack. Do not stack dishes on top of each other as water must
have free access to all sides of every dish. Stand plates edgewise in a peg-type rack (Figure 7). Cups, glasses
and bowls should lay upside down in an open or compartment-type rack (Figure 7). Silverware and other small
pieces should lay loosely on the bottom of a flat-bottom rack. Do not allow foreign objects to enter the unit,
especially metallic contaminants such as staples and paper clips.
Check to see if any detergent, rinse aid or sanitizer chemicals need to be replenished. Use only commercial-type
detergents, as prescribed by your chemical professional.
COARSE STRAINER FINE STRAINER
Figure 7

20 | STERO UNDERCOUNTER DISHWASHER & GLASSWASHER
DO’S AND DON’TS FOR YOUR NEW STERO DISHWASHER
DO assure proper water hardness.
DO prescrape dishes thoroughly.
DO use only detergents recommended by your chemical professional.
DO, at the end of the day, thoroughly clean the machine, rinse and dry. (Leave door open.)
DO use only products formulated to be safe on stainless steel.
DO NOT use detergents formulated for residential dishwashers.
DO NOT allow food soil to accumulate on the tank bottom.
DO NOT exceed chemical manufacturer’s recommended concentrations for detergent, sanitizer,
rinse aid or lime scale remover.
DO NOT use steel wool to clean ware or warewasher surface.
DO NOT allow foreign objects to enter the unit, especially metallic contaminants.
CLEANING
This machine must be cleaned at least once each working day. Use only products formulated to be safe
on stainless steel.
1. Press POWER. The machine will drain. When the display is no
longer lit, open the door and remove any debris from the
bottom of the tank. Do not allow food soil to accumulate on
the tank bottom.
2. Remove the lower rinse arm by unscrewing the thumb nut
(Figure 8). Remove the lower wash arm by pulling the arm off
the shaft. Remove the upper rinse and wash arms in the same
manner. Remove the coarse and fine strainers (see Figures 5
and 6). Thoroughly clean these items in a sink. Remove debris
from wash/rinse arm nozzles.
3. With a damp cloth, wipe the interior of the machine. DO NOT
use steel wool. Wipe the exterior of the machine. Remove any
remaining debris with a mild cleanser formulated for stainless
steel and a soft cloth or brush.
4. Replace the fine and coarse strainers. Reinstall the lower wash arm by pushing it down on the shaft.
Place the lower rinse arm on the shaft and securely tighten the thumb nut. Spin arms to make sure they
spin freely. Repeat this procedure with the upper wash and rinse arms.
5. Use a soft, damp cloth or sponge and mild cleanser to clean the control keypad and display. DO NOT use
abrasive or harsh cleaners or scouring pads.
6. Leave the door ajar overnight to allow the interior to air out and dry. The door design allows for the door
to remain partially open and can be used to vent the machine at the end of the day.
THUMB NUT
Figure 8