Accu-Steam G2 User manual

AccuTemp Products, Inc. · 8415 North Clinton Park · Fort Wayne, IN 46825 ·800 210-5907 · accutemp.net
SERVICE MANUAL
ACCU-STEAM GAS G2 GRIDDLE
Improper installation, alteration,
adjustment,service, cleaning or maintenance
of this commercial appliance could result in
property damage, serious injury or death.
Read and understand the installation, operational,
maintenance instructions before installing,
servicing, or operating this commercial
appliance.
Serial Number:
Model:
Install Date:
WARNING
Record the serial number, model number (identication
decal located on the left side panel of the commercial
appliance) , voltage and the install date. Please have
this information when calling for assistance.
NOTE

Accu-Steam™ G2 Gas Service Manual
PAGE 2 SP8042-1609
Toll Free 800.480.0415
Ofce 260.469.3040
Fax [phone]
Email [email protected]
Web Site www.accutemp.net

Accu-Steam™ G2 Gas Service Manual PAGE 3
SP8042-1609
WARNING SYMBOL DEFINITIONS
SYMBOL DEFINITIONS
Symbols are used to attract your attention to possible dangers. They are only effective if
the operator uses proper accident prevention measures. Some of the symbols are boxed
text; while others maybe just picture icons. Please give this information the respect they
deserve for safe operation.
Indicates a potentially hazardous situation;
which, if unchanged, will result in death or
serious injury.
WARNING
Indicates an imminently hazardous situation;
which, if unchanged, will result in death or
serious injury.
DANGER
Indicates a potentially hazardous situation;
which, if unchanged, will result in minor or
moderate injury.
CAUTION
Advises the reader of information or
instructions, vital to the operation or
maintenance of the equipment.
NOTE
Warning Text Boxes
Below are denitions of the warning text boxes.
Symbol Icons
Below are denitions of the symbol icons used
in this manual.
ALERT
Noties the reader of an import-
ant message or warning; usually a
safety related message.
INFORMATION
Noties the reader of an important
information that may or may not
be safety related.
CAUTION -
HOT SURFACE
DANGEROUS
VOLTAGE
EARTH GROUND

Accu-Steam™ G2 Gas Service Manual
PAGE 4 SP8042-1609
ELECTRICAL SHOCK HAZARD WHILE WORKING ON
ENERGIZED EQUIPMENT.
Unplug equipment prior to removing any components effected by electricity.
PERSONNEL INJURY HAZARD WHILE PICKING UP OR
MOVING HEAVY EQUIPMENT.
Always use at least 2 people and proper lifting techniques when picking-up, moving, or
ipping-over heavy equipment.
DANGER
SAFETY PRECAUTIONS

Accu-Steam™ G2 Gas Service Manual PAGE 5
SP8042-1609
DO NOT store or use Gasoline, or any other Flammable Vapor and/or Liquids in the vicinity of this
or any other appliance.
WARNING
In the event of a Power Failure, DO NOT attempt to operate this appliance.
WARNING
IMPROPER installation, adjustment, alteration, service, or maintenance can cause personal injury
or death; and/or property damage. Read the installation, operation, and service/maintenance
instructions thoroughly; before installing or servicing this equipment.
WARNING
Only QUALIFIED service technicians/electricians should perform the equipment installation, to
ensure that all electrical and safety requirements are met; and that all wiring is performed in
accordance with all national, state, and local electrical codes.
WARNING
IMPORTANT FOR YOUR SAFETY
The Safety Instructions listed on this page below, should be posted
in a prominent location as a reminder of safe practices; as well as,
recommended actions to follow in the event of an equipment
or facility’s utility issue.

Accu-Steam™ G2 Gas Service Manual
PAGE 6 SP8042-1609
WARNING & CAUTION NOTES
ONLY QUALIFIED SERVICE TECHNICIANS SHOULD PERFORM MAINTENANCE ON THIS
EQUIPMENT.
WARNING
CAUTION
GRIDDLE MAY HAVE SHARP EDGES.

Accu-Steam™ G2 Gas Service Manual PAGE 7
SP8042-1609
Table of Contents
Sequence of Operation .............................................................................................................
Specication Sheet ...................................................................................................................
Troubleshooting Guide .............................................................................................................
Digital Controller .....................................................................................................................
Replaceable Components .........................................................................................................
Parts Identication, Removal and Installation
-Fuses .......................................................................................................................................
-Control Relay ..........................................................................................................................
-Control Board .........................................................................................................................
-Hi_Limit Control Board .........................................................................................................
-Transformer ............................................................................................................................
-Heat Lamp ..............................................................................................................................
-Fault Timer .............................................................................................................................
-Gas Valve ...............................................................................................................................
-Ignition Control Module ........................................................................................................
-Flame Sensor .........................................................................................................................
-Igniter .....................................................................................................................................
-Infrared Burner .....................................................................................................................
-RTD Sensor(s) ........................................................................................................................
Testing
-RTD ........................................................................................................................................
-Flame Sense ...........................................................................................................................
-Gas Pressure ..........................................................................................................................
Preventative Maintenance ........................................................................................................
Schematic ................................................................................................................................
Warranty .................................................................................................................................
8-9
9
10-12
13-14
15
16
16
17
17
18
18
18
19
19
20
20
20
21
21
22
23
24
24
26

Accu-Steam™ G2 Gas Service Manual
PAGE 8 SP8042-1609
Sequence of Operation
1. When the G2 griddle is plugged in, AC line voltage is supplied to the primary side of the
transformer.
2. The voltage out of the secondary side of the transformer is 24VAC nominal. Yellow and blue
wires out of the transformer.
3. The blue leg of the secondary side of the transformer (24VAC) is connected to the yellow
system harness, is split and is connected to the combination gas valve coils, remote timer connector
and the Hi-Limit thermostat.
4. From the HI-Limit thermostat the 24VAC leg is daisy chained to the, heat lamp, the main
digital control board and to chassis ground.
5. The yellow secondary leg of power from the transformer connects to the violet system
harness and goes to the Hi-Limit, then daisy chains over to the main digital control board. At this
time the system is waiting to be powered on via the Digital control board.
6. Upon pressing the “ON” button on the digital controller, the digital controller powers up and
a relay on the digital controller is closed making a connection between the violet 24VAC leg and
the input of the HI-Limit thermostat through the white with brown striped harness.
7. If the reading from the Hi-Limit RTD (Resistive Thermal Device) is not 425°F or higher, an
output relay in the Hi-Limit controller will be closed causing the 24VAC to be sent to the ignition
control, DC relay and to the pilot valve coil of the gas combination valve, opening the pilot valve.
8. If the reading from the Hi-Limit RTD (Resistive Thermal Device) is 425°F or higher, an
output relay in the Hi-Limit controller will be opened causing the 24VAC to be cut off from the
ignition control, DC relay and to the pilot valve coil of the gas combination valve, closing the pilot
valve.
9. The over temperature lamp is connected across the common and the normally open contacts
of the High Limit thermostat output relay. When the relay is activated or closed, the griddle
temperature is below 425°F, there is 24VAC on both sides of the over temp lamp, preventing it
from lighting up. If the High Limit thermostat output relay is deactivated or open, the griddle
temperature is at or above 425°F, the lamp will see the voltage potential from the chassis ground/
yellow system harness side of the transformer through the pilot valve coil and light up.
10. If the digital controller senses the griddle temperature is below the set point temperature via
the digital controller RTD sensor, the controller will output 24VDC to the ignition control DC coil
relay and allow 24VAC to be sent to the ignition module via the blue harness to pin 2 of the ignition
module, which is daisy chained to the ignition fault indicator lamp.
11. The ignition module will begin the ignition sequence by initiating a spark at the ignition probe
first then it will send 24VAC, via the red harness from pin #1 of the ignition module to the heat
lamp, which is daisy chained to the main gas valve coil of the combination gas valve through the
red system harness. This allows gas to flow through the combination gas valve, through the orifices
in each main burner and through the main burner tiles.
12. When the gas air mixture is ignited, the flame sense probe will detect a DC voltage level
through the flame’s ionized gas to ground via the orange flame sense harness to the ignition
module, pin #6.

Accu-Steam™ G2 Gas Service Manual PAGE 9
SP8042-1609
Griddle Specications Sheet
13. If the DC voltage level is detected before 4 seconds and is at a high enough level the ignition
module will continue to hold the main gas valve open.
14. If the DC voltage level is not high enough within the 4 second window, the ignition module
will shut down the main gas valve.
15. A fault timer is connected across the red and blue harnesses from the ignition module. When
the ignition module is commanded to start the ignition cycle, 24VAC is present on both the red and
the blue harnesses and the timer is deactivated.
16. If the ignition module fails to see a sufficiently high enough DC voltage level through the
flame sense circuit, the ignition module will disable 24VAC from the red harness and the timer will
see the voltage potential from the chassis ground/yellow system harness side of the transformer
and begin an approximate 6 second timer sequence that controls the ignition fault indicator lamp
causing it to flash.
17. When the griddle heats up to the set point temperature, the digital controller RTD resistance
changes and provides a signal to the control board telling it that the set point temperature has been
reached.
18. When the digital controller sees the resistance value for the set point temperature, it cuts
power to the ignition control DC coil relay and breaks the connection to the ignition module
causing the griddle to stop heating further.
Sequence of Operation

Accu-Steam™ G2 Gas Service Manual
PAGE 10 SP8042-1609
Troubleshooting Guide
UNI T ON?
CORRECT
VOLT AG E
CHECK
INTERNAL
VOLT AG E
A
B
C
NO
NO
BREAKER ON?
UNIT PLUGGED
IN?
YES
YES
NO
NO
FAULT LIGHT/
ERROR CODE?
D
E
OVE RTEMP? YES
HE AT ON?
H
I
NO
UNIT HEATING
UP?
HEAT LIGHT ON?
YES
NO
NO
ERROR CODE
E001?
E002?
PROPER
TEMPERATURE
UNI T
OPERATING
NORMAL
J
YES
NO
NO
YES
YES
YES
YES NO
FAULT LIGHT
FLASHING F
FAULT LIGHT ON G
YES
NO
NO
YES

Accu-Steam™ G2 Gas Service Manual PAGE 11
SP8042-1609
Troubleshooting Guide
APower cord
disconnected
Conrm proper voltage at outlet.
Plug in power cord.
BBreaker is
tripped
Unplug griddle and check line voltage at outlet.
Reset breaker.
C
Temperature
Controller
If 24VAC is on secondary side of transformer, check power input terminals of Temp
Controller J2-1 & J2-2.
If 24VAC is at terminals, replace Temp Controller.
If 24VAC is not at terminals, check for broken wires or poor crimps at the terminals.
If no 24VDC at the terminals, measure across the controller outputs J7-1 and J7-2 for
24VDC.
If no voltage, replace controller.
If there is voltage, check for poor crimps or loose wires at the terminals.
Fuses Check for loose or blown fuses.
Wiring Inspect wiring for damage, opens and/or shorts. Inspect ground and wire to wire
connections.
Note* Unit has a digital controller, if voltages, fuses and wiring appear to be in order,
try cycling power.
Transformer Check for 24 Volts from secondary side of transformer. If input to transformer is
present and there is no output, replace transformer.
D
Error Code
E001 or E002
on display
E001: Open Temp (RTD) sensor J3-1 & J3-2. Check terminals for poor crimping.
E002: Shorted Temp (RTD) sensor J3-1 & J3-2.
If RTD checks good, reconnect RTD and cycle power. Is error code still present?
Replace Temperature Controller.
E
Over temp
indicator
If griddle is not warming up or holding a set point temperature, cycle power.
Check Over Temp RTD for proper values at current temperature.
If temp/resistance values match RTD, replace Over Temp Thermostat.
If values do not match RTD, replace Over Temp RTD.
If Over Temp and Heat light are on and griddle is not warming, cycle power.
If Over Temp light goes out, monitor griddle to see if it over temps again.
If temperature is greater than 50 degrees different than measurement device, verify
measurement device.
If measurement device appears to be accurate, measure RTD.
If RTD measures normally, replace temperature controller.
If RTD measures out of specications, replace RTD.
F
Fault light
ashing
If burners did not ignite, check gas pressure, cycle power.
If burners did ignite and unit is heating, check for poor connections in the harness at
the fault timer relay.

Accu-Steam™ G2 Gas Service Manual
PAGE 12 SP8042-1609
Troubleshooting Guide
G
Fault light on If burners did not ignite, replace fault timer.
If burners did ignite and unit heating, check for short to ground in the white wire
connected to the fault indicator lamp.
H
Heat light not
on
If griddle is warming up or regulating at a set point, replace indicator lamp.
If griddle is not warming up or regulating at a set point, check to see if temp demand ice
cube (24VDC) relay is engaged.
If ice cube relay is not engaged, check for 24VDC at terminals 7 & 8 from temperature
controller.
If voltage is at relay coil, replace relay.
If voltage is not at relay coil, replace temperature controller.
If ice cube relay is engaged, check for poor connections or broken wires. Blue wires com-
ing from ignition module or brown wire coming from OT thermostat.
If connections are good, replace relay.
I
Unit not heat-
ing up
Check for 24 VAC to the gas valve.
If no voltage to the gas valve check for poor or loose connections or broken red wire
between the “heat” lamp and the gas valve.
If there is voltage to the red wire of the gas valve, check for voltage at the brown wire of
the gas valve.
If there is 24VAC to the brown wire at the gas valve and the valve has not turned on,
replace the gas valve.
If there is 24VAC to the brown wire at the gas valve and the valve has turned on, check for
proper gas supply and pressures.
If there is no 24VAC on the brown wire at the gas valve, check for poor or loose
connections or broken brown wire at the gas valve, the “OT” indicator lamp and the OT
thermostat and the demand relay. Repair as necessary.
J
Inaccurate
Temperature
If display temperature is greater than 50 degrees different than measurement device, verify
measurement device. If measurement device appears to be accurate, measure RTD.
If RTD measures normally, replace temperature controller.
If RTD measures out of specications (temp/resistance), replace RTD.

Accu-Steam™ G2 Gas Service Manual PAGE 13
SP8042-1609
Digital Controller
Change Cooking/ Default/ Preset Temperatures
1. Turn the griddle on by pressing the ON/OFF (S5) button.
2. Hold the UP (S1) arrow in for 3 seconds until all 3 lights start to ash.
3. Press the UP (S1) or DOWN (S4) arrow until desired temp is displayed.*
4. Once the desired temp is displayed it can be saved as a preset temperature by immediately holding down
PRESET TEMP 1 (S2) or PRESET TEMP 2 (S3), until unit shuts off. It can also be save as the default on
temp by turning off the griddle
Lock/Unlocked Note*
If temperature is unable to be adjusted, user may need to unlock the system by holding down the
ON/OFF (S5) button and Temp (S6) button together for 8 seconds or until “ULOC” is displayed. Once the
temperatures are saved, it is recommend the user locks the system by holding down the
ON/OFF (S5) button and Temp (S6) button together for 8 seconds or until “LOC” is displayed. This will allow
the cooks to only use the preferred settings.
NOTE:
Unplug griddle from wall receptacle before replacing the control
board in order to prevent damage to equipment.
When power is applied to the control, the control will congure itself to operate in accordance with the
parameters stored in memory. These parameters may be adjusted using Manager’s Mode.

Accu-Steam™ G2 Gas Service Manual
PAGE 14 SP8042-1609
Digital Controller
Operating Mode
When power is applied to the control, the control will congure itself to operate in accordance with the parame-
ters stored in memory. These parameters may be adjusted using Manager’s Mode.
Reset
Pressing and holding the DOWN (S4) arrow key and the ON/OFF (S5) key for ve seconds will reset the soft-
ware back to the factory default settings.
Error Codes
The control will display error codes for the following conditions:
E001 Displays when controller detects an Open Sensor
E002 Displays when controller detects a Shorted Sensor
9999 No calibration data stored or invalid calibration data detected
To reset from any error, unit must be turned OFF, repaired, and then turned ON.
When any error is displayed, outputs are forced open. The following chart illustrates the programming logic and
program level indication:

Accu-Steam™ G2 Gas Service Manual PAGE 15
SP8042-1609
Main Components and Purpose Refer ence
Transformer
AT0E-2662-5
-Steps down the line voltage to approximately 24VAC
nominal
Timer, Ignition Fault
AT0E-2500-3
-Controls fault light.
-If signal is lost from the ignition module the timer
causes ignition fault light to turn on
Control Relay, 24vdc
AT0E-2625-6
-Controls input signal to ignition module.
-Coil side of relay is energized by digital control board.
Infrared Burner - Gas (36” & 48”)
AT2B-2099-2
-Supplies heat to the griddles steam chamber
- Supplies ame for ame sensor
Flame Sensor
AT2E-4717-2
-When in direct contact with the ame, the sensors gives
off a DC Millivolt or DC Micro amp signal to the
ignition module.
Igniter
A22E-4716-1
-Receives voltage from ignition module.
- Ignites burners. (1/8”-3/16” Gap)
Natural Gas Valve, 5” WC (H20)
AT2E-1806-2
-Regulates incoming gas pressure (1/2lb or 14”WC max
unregulated incoming pressure)
-First valve opens when control board is powered on and
the second valve opens and supplies gas to the burners
when the control board calls for heat.
Ignition Control Module
AT2E-1807-1
-Takes reading from the ame sensor.
-Receives input from temperature Controller and
Hi-Limit.
-Sends voltage to the igniter.
-Controls gas valve and heat lamp
Digital Control Board
AT0E-3625-5
-Receives input signal from RTD Temperature Sensor.
-Pulls in relay which controls the ignition module.
Fuse .75 Amp 250v
AT0E-2731-4
-The .75A fuse is to provide protection to the control cir-
cuitry in case of a short in the system.
Hi-Limit Control Board
AT0E-3880-1
-Receives input signal from Hi-Limit RTD temperature
sensor
-Cuts power to ignition module when unsafe signal
is met from Hi-Limit RTD (approximatively 425° or
182Ω)
Temperature Sensor RTD
AT0E-2885-8
(Black heat shrink sleeve for 1000Ω identication)
- The RTD provide temperature reference information to
the Temperature Control. This RTD is a 1000Ω.
Hi-Limit Temperature Sensor, RTD
AT0E-2885-7
(Red heat shrink sleeve for 100Ω identication)
- The RTD provide temperature reference information to
the Hi-Limit Board. This RTD is a 100Ω.
Heat Lamp 24v Red
AT0E-1800-2
-Receives 24VAC power from the ignition module and
indicates the valve is open.

Accu-Steam™ G2 Gas Service Manual
PAGE 16 SP8042-1609
Parts Identication, Removal and Installa tion
Fuse .75 Amp 250V
AT0E-2731-4
1. Unplug from wall receptacle.
2. Lower front access panel by removing the screws
in the upper corners of the panel.
3. Replace fuse.
Hi-Limit RTD Temp Sensor RTD Igniter
Fuse Block Transformer Fault Timer Hi-Limit Control board Ignition Control Module
Main Control Board
Control Relay
Control Valves Tap
Control Relay
AT0E-2825-6
1. Unplug from wall receptacle.
2. Lower front access panel by removing the screws in
the upper corners of the panel.
3. Take note of wire location
4. Remove wires and hardware securing relay.
5. Reinstall in reverse order.

Accu-Steam™ G2 Gas Service Manual PAGE 17
SP8042-1609
Parts Identication, Removal and Installa tion
Digital Control Board
AT0E-3625-5
1. Unplug from wall receptacle.
2. Lower front access panel by removing the screws in
the upper corners of the panel.
3. Locate the main control board. Take note of wires
and their terminals, remove wires.
4. Remove nuts and washers securing board to panel,
remove panel.
5. Reinstall in reverse order.
Hi-Limit Control Board
AT0E-3880-1
1. Unplug from wall receptacle.
2. Lower front access panel by removing the screws in
the upper corners of the panel.
3. Locate the Hi-Limit control board. Take note of
wires and their terminals, remove wires.
4. Remove nuts and washers securing board to panel,
remove panel.
5. Reinstall in reverse order.
IMPORTANT NOTICE: Failure to unplug the unit
before pulling wires from the board could result in
fatal damage to the controller.

Accu-Steam™ G2 Gas Service Manual
PAGE 18 SP8042-1609
Parts Identication, Removal and Installa tion
Heat Lamp
AT0E-1800-2
Hi-Limit Lamp
AT0E-1800-2
Fault Lamp
AT0E-1800-2
1. Unplug from wall receptacle.
2. Lower front access panel by removing the screws in
the upper corners of the panel.
3. Locate the light bar and remove wires from lamp.
4. Remove nuts securing the light bar to the front
panel.
5. Remove lamp.
6. Reinstall in reverse order.
1. Unplug from wall receptacle.
2. Lower front access panel by removing the screws in
the upper corners of the panel.
3. Locate transformer and note the location of the
wires and their terminals, disconnect wires.
4. Removed nuts securing transformer.
5. Remove transformer.
6. Reinstall in reverse order.
Transformer
AT0E-2662-5
Fault Timer
ATOE-2500-3
1. Unplug from wall receptacle.
2. Lower front access panel by removing the screws in
the upper corners of the panel.
3. Locate the Fault timer, take note of wire location
and remove wires.
4. Remove hardware securing timer.
5. Remove timer.
6. Reinstall in reverse order.
7. Set timer pot to 6 seconds.

Accu-Steam™ G2 Gas Service Manual PAGE 19
SP8042-1609
Parts Identication, Removal and Installa tion
Gas Valve
AT2E-1806-2
Ignition Control Module
AT2E-1807-1
1. Unplug from wall receptacle.
2. Lower front access panel by removing the screws in
the upper corners of the panel.
3. Locate the module and remove wires.
4. Remove hardware securing module.
5. Remove module.
6. Reinstall in reverse order.
1. Unplug from wall receptacle.
2. Turn off gas supply and disconnect the unit from
supply hose.
3. Lower front access panel by removing the
screws in the upper corners of the panel.
4. Take note of or mark wire location and remove
wires.
5. Disconnect brass gas lines from cross tting
6. Disconnect union and remove assembly
7. Remove cross tting
8. Reinstall in revers order; applying new pipe
dope to ttings

Accu-Steam™ G2 Gas Service Manual
PAGE 20 SP8042-1609
Parts Identication, Removal and Installa tion
Flame Sensor
AT2E-4717-1
Igniter
AT2E-4716-1
Infrared Burner
AT2B-2099-2
1. Unplug from wall receptacle.
2. Lower front access panel by removing the
screws in the upper corners of the panel.
3. Remove orange ame sense wire.
4. Remove screws and ame sensor
5. Reinstall in reverse order.
1. Unplug from wall receptacle.
2. Lower front access panel by removing the
screws in the upper corners of the panel.
3. Remove igniter wire
4. Remove screws and igniter
5. Reinstall in reverse order.
6. Set new igniter gap between 1/8”-3/16’’
1. Unplug from wall receptacle.
2. Turn off gas supply and disconnect the unit from
supply hose.
3. Remove gas line at venture
4. Remove front 2 nuts fully and loosen back 2
nuts securing burner
5. Remove Burner
6. Reinstall in reverse order.
Note: When diagnosing a bad burner, often
times the exterior back side of the burner will
have black or gray discoloration in a circular
or half moon shaped pattern.