Garland MCO-E-5 Service Manual
Service Manual For MCO GS/GD
Full Size "Gas" Convection Ovens
With 200, 410, 450, 455, 470, 475 Series
Controllers
GARLAND COMMERCIAL INDUSTRIES
185 East South Street
Freeland, Pennsylvania 18224
Phone: (570) 636-1000
Fax: (570) 636-3903
Part # MCOSM06 Rev 1(11/03/08) © 2006 Garland Commercial Industries, Inc.
GARLAND COMMERCIAL RANGES, LTD.
1177 Kamato Road, Mississauga, Ontario L4W 1X4
CANADA
Phone: 905-624-0260
Fax: 905-624-5669
Enodis UK LTD.
Swalloweld Way, Hayes, Middlesex UB3 1DQ ENGLAND
Telephone: 081-561-0433
Fax: 081-848-0041
Page 2
Part # MCOSM06 Rev 1 (11/03/08)
TABLE OF CONTENTS
Section One Operation Manual .................................................5
Contents....................................................................................6
Dimensions & Specications
Installation
Operation
Performance Recommendations
Cooking Guide
Cook And Hold
Problems / Solutions
Cleaning & Maintenance
Motor Care
..................................................................................8
.................................................................................12
.............................................................................22
.............................................................................23
.......................................................................24
.................................................................................26
Section Two Electronic Pilot & Main Burner .....................................27
Ignition Sequence..........................................................................28
Trouble Shooting Table
Service
G77x Intermittent Pilot Controls
G76x Direct Spark Ignition Controls
....................................................................................30
.................................................................7
............................................................21
....................................................................25
.....................................................................29
.............................................................32
.........................................................35
Section Three Temperature Calibration.........................................39
General Calibration.........................................................................40
200 & 300 Series Controllers Calibration
.....................................................41
Section Four Convection Oven Components ....................................43
Doors......................................................................................44
Door Latch Mechanism
Motor
Door Microswitch
Probes
Key Pad Test
Mco Convection Oven Gas Valve
Relay Boards . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54
Controls
.....................................................................................48
.....................................................................................51
...............................................................................52
...................................................................................57
.....................................................................47
..........................................................................50
............................................................53
Section Five Trouble Shooting .................................................59
Controller Operational Tests ................................................................60
Controller Fault Finding
Additional Notes
General Trouble Shooting Guide
...........................................................................63
....................................................................61
............................................................64
Section Six Service Bulletins ...................................................67
Section Seven Wiring Diagrams
Part # MCOSM06 Rev 1 (11/03/08) Page 3
...............................................101
Page 4
Part # MCOSM06 Rev 1 (11/03/08)
Section One
Operation
Manual
Part # MCOSM06 Rev 1 (11/03/08) Page 5
CONGRATULATIONS! You have just purchased the nest commercial cooking equipment available anywhere.
Like any other ne, precision built appliance, it should be given regular care and maintenance. Periodic inspections by your
dealer or a qualied service agency is recommended. When corresponding with the factory or your local authorized factory
service center regarding service problems or replacement parts, be sure to refer to the particular unit by the correct model
number (including the prex and sux letters and numbers) and the warranty serial number. The rating plate axed to the
unit contains this information.
CONTENTS
DIMENSIONS & SPECIFICATIONS ...............7
INSTALLATION ................................8
Installation Notes: .....................................8
Installation Of Ovens Equipped With Casters ...........8
Installation Of Double Deck Models . . . . . . . . . . . . . . . . . . . 8
Gas Connection .......................................9
Electrical Connection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Ventilation & Air Supply . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Testing & Lighting Instructions . . . . . . . . . . . . . . . . . . . . . . . 11
OPERATION..................................12
Master 200 Mechanical Control with Timer ............12
In O Mode: ..................................... 12
Start Up:......................................... 12
Fan Speed:....................................... 12
Lights: ........................................... 12
Cool Down: ...................................... 12
Temperature: .................................... 12
Timer: ...........................................12
MASTER 300 Solid State Control ......................13
In O Mode: ..................................... 13
On Start Up: ..................................... 13
Controller Keys .................................. 13
MASTER 410,450, 455 CONTROLS .....................14
In O Mode: ..................................... 14
On Start Up: ..................................... 14
Operating the Controls........................... 15
Cook-N-Hold Operation.......................... 15
Core Probe Operation............................ 16
CHANGING FACTORY SETBACK PROGRAM ........ 16
MASTER 470/475 CONTROLS ..........................17
Manual cooking: ................................. 17
Manual cooking using Cook-N-Hold: ............. 17
Programming Product Keys (Master 475): ......... 17
Programming Product Keys (Master 470): ......... 19
Cooking Using The Product Keys(475 and r 470): .. 19
Verifying hold time (475 and 470): ................ 19
Cooking with the Shelf Timer (475 and 470): ......20
PERFORMANCE RECOMMENDATIONS .........21
COOKING GUIDE.............................22
COOK AND HOLD ............................23
PROBLEMS / SOLUTIONS .....................24
CLEANING & MAINTENANCE ..................25
Break-In Period . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .25
Exterior Cleaning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .25
Interior Cleaning .....................................25
Fan Area Maintenance. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .25
MOTOR CARE ................................26
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Part # MCOSM06 Rev 1 (11/03/08)
7-3/4"
[197mm]
38-1/4"
[972mm]
3/4"
[19mm]
17-3/4"
[451mm]
TOP VIEW
2"
[51mm]
FLUE: 2-3/8" x 5"
[60mm x 127mm]
3/4" N.PT.
GAS INLET
11-1/2"
[292mm]
38"
[965mm]
32-1/8"
[816mm]
25-3/8"
[645mm]
SINGLE DECK
FR ONT VIEW
1-1/4"
[32mm]
34"
[864mm]
54-9/16"
[1386mm]
3/4" REAR
GAS INLET
32-1/8"
[816mm]
32-1/8"
[816mm]
6-1/4"
[159mm]
14-3/4"
[375mm]
32-1/8"
[816mm]
35-7/16”
[900mm]
32-1/8"
[816mm]
1-1/4"
[32mm]
DOUBLE DECK
FR ONT VIEW
D
H
H
1" REAR
GAS INLET
DIMENSIONS & SPECIFICATIONS
Single-Deck
Models
Int. Dimensions :In (mm) Ext. Dimensions: In (mm) Ship Wt Ship Dim.
W H D W H * D Lbs/kg Cubic Ft.
Standard Depth 29 (736) 24 (610) 24 (610) 38 (965) 57-1/2 (1461) 41-1/4(1048) 600/273 64
Deep Depth 29 (736) 24 (610) 28 (711) 38 (965) 57-1/2 (1461) 44-1/2(1130) 600/273 64
Double-Deck
Models
Int. Dimensions: In (mm) Ext. Dimensions: In (mm) Ship Wt. Ship Dim.
W H D W H * D 2@Lbs/kg Cubic Ft.
Standard Depth 29 (736) 24 (610) 24 (610) 38 (965) 70-1/2 (1791) 41-1/4(1048) 1150/523 128
Deep Depth 29 (736) 24 (610) 28 (711) 38 (965) 70-1/2 (1791) 44-1/2(1130) 1150/523 128
*Height with or without standard casters. Height with low prole casters (double deck) is 68-1/2" (1740mm).
Input Ratings, Nat & Pro Electrical Specications
Models
BTU/hr
kW Equiv. Gas Inlet 120V/1Ph. 240V/1Ph.
Single Deck 60,000 17. 6 (1 )@ 3/4" NPT (1)@9.4A (1)@ 5.2A
Double Deck 120,000 35.2 (1 )@1" NPT (2)@9.4A (2)@ 5.2A
(Includes
fan motor)
Installation Notes:
Combustible Wall Clearances:
Sides: 1" (25mm)
Back: 3" (76mm)
Entry Clearance:
Crated: 47" (1194mm)
Notes:
Uncrated: 32-1/2" (826mm)
Operating Pressure:
Natural: 4.5" WC (11 mbar)
Propane: 10" WC (25 mbar)
Max 13.8" WC @ 70°F (21°C)
NOTE: Data applies only to
North America
1. Standard electrical specications include motor requirements.
2. (120V units) 115V 3/4 HP, 2-speed motor; 1140 and 1725 rpm 60Hz
3. (240V uni ts) 2 00-240 V, 3/4 HP, 2-spe ed motor; 1140 and 1725 rp m, 6 0Hz
4. A 6 ft. line cord is provided for each 120V deck with a (NEMA #5-15P) plug.
5. Garland recommends a separate 15 AMP circuit for each 120V unit.
Gas Input ratings shown here are for installations up to 2,000-ft. (610m) above sea level. Specify altitudes over 2,000 ft.
Commercial cooking equipment requires an adequate ventilation system. For additional information, refer to the National Fire
Protection Association’s standard NFPA96, "Vapor Removal from Cooking Equipment." (NOTE: For North America only)
Please specify gas type when ordering.
Part # MCOSM06 Rev 1 (11/03/08) Page 7
INSTALLATION
Installation Notes:
Combustible and Non-Combustible Wall Clearance: Side:
1.0" (25 mm) Rear: 3.0" (76 mm)
NOTE: Adequate clearance must be provided for servicing
and proper operation.
The importance of the proper installation of Commercial
Gas Cooking Equipment cannot be over stressed. Proper
performance of the equipment is dependent, in great part,
on the compliance of the installation with the manufacturer's
specications. Installation must conform to local codes or,
in the absence of local codes, with the National Fuel Code,
ANSI Z223.1, Natural Gas Installation Code, CAN/CGA-B149.1,
or the Propane Installation Code, CAN/CGA-B149.2, as
applicable.
Before assembly and connection, check gas supply.
A. The type of gas for which the unit is equipped is stamped
on the data plate located behind lower front panel.
Connect a unit stamped "NAT" only to natural gas;
connect a unit stamped "PRO" only to propane.
B. If it is a new installation, have gas authorities check meter
size and piping to assure that the unit is supplied with
sucient amount of gas pressure required to operate the
unit.
C. If it is additional or replacement equipment, have gas
authorities check pressure to make certain that existing
meter and piping will supply fuel at the unit with not
more that 1/2" water column pressure drop.
NOTE: When checking pressure be sure that all other
equipment on the same gas line is on. A pressure regulator
is supplied with GARLAND Convection Ovens. Regulator is
preset to deliver gas at pressure shown on the rating plate.
The appliance and its individual shut-o valve must be
disconnected from the gas supply piping system during
any pressure testing of that system at test pressures in
excess of 1/2 PSI (3.45 kPa).
The appliance must be isolated from the gas supply
piping system by closing its individual manual shut-o
valve during any pressure testing of the gas supply piping
system at test pressures equal to or less than 1/2 PSI
(3.45 kPa).
Installation Of Ovens Equipped With Casters
A. For an appliance equipped with casters, the installation
shall be made with a connector that complies with the
Standard for Connectors for Movable Appliances, ANSI
Z21.69 or Connectors for Moveable Gas Appliances,
CAN/CGA-6.16, and a quick-disconnect device that
complies with the Standard for Quick-Disconnect Devices
for Use With Gas Fuel, ANSI Z21.41, or Quick-Disconnect
Devices for Use with Gas Fuel, CAN1-6.9, and adequate
means must be provided to limit the movement of the
appliance without depending on the connector and the
quick-disconnect device or its associated piping to limit
the appliance movement and the location(s) where the
restraining means may be attached to the appliance shall
be specied.
B. The front casters of the unit are equipped with brakes
to limit the movement of the oven without depending
on the connector and any quick-disconnect device or its
associated piping to limit the appliance movement.
C. The restraint can be attached to the unit near the gas inlet.
If the restraint is disconnected, be sure to reconnect the
restraint after the oven has been returned to its originally
installed position.
Installation Of Double Deck Models
A. Position insert in bottom leg opening and tap insert up
into leg till it seats at collar. Attach six inch (6") legs to
lower oven section. Raise unit or lay on its left side. Place
the front legs on the oven so as to line up with four (4)
attaching bolt holes. Secure leg to oven frame using (4)
3/8-16 x 3/4 bolts and washers provided. Repeat at rear of
unit.
B. Remove lower front cover of top deck (located under oven
doors). Raise top deck into place and line up body sides
and back of the unit. Fasten the rear of the units together,
with the stacking bracket, as shown, using (6) 1/4-20
machine screws, lock washers and nuts, (provided).
C. Install the interconnecting ue parts, carefully following
the instructions contained in the stacking kit. Pay
particular attention to the type of ovens you are stacking
and be sure to follow the corresponding instructions.
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Part # MCOSM06 Rev 1 (11/03/08)
D. Assemble the stacking pipes provided in the stacking
3/4" Union
3" Nipple
3" Nipple
90 Degree Street Elbow
90 Degree Street Elbow
20-1/2" Nipple
3/4" to 1" Bell Reducer
kit as shown in the diagram at the top of this page. This
allows both ovens to be supplied by a single gas line. The
minimum recommended size of a single supply line for
two stacked ovens is 1 inch. Use a pipe thread compound
that is intended for use on propane gas piping and be sure
to check for leaks before nalizing the installation.
E. Check leveling of unit four (4) ways (using a common
carpenter's level on the rack inside the oven).
F. Plug the cord set of each unit into a 115-Volt power supply
outlet.
IMPORTANT
All gas burners and pilots need sufficient
air to operate and large objects should not
be placed in front of this oven, which would
obstruct the airflow through the front.
Objects should not be placed on main top rear
of oven while in use. This could obstruct the
venting system of the unit's flue products.
Gas Connection
G. Maintain clearance from combustibles.
Each gas appliance shall be located with respect to building
construction and other equipment so as to permit access to
the appliance. Such access and clearance may be necessary
for servicing and cleaning.
The 1" NPT inlet at the rear must be considered in piping the
gas supply for double stack units or 3/4" NPT for individual (or
single deck) connections. Undersized gas supply line(s) may
restrict the gas supply and aect performance. If other gas
appliances are supplied by the same supply line, the supply
line must be sized to carry the combined volume without
causing more than 1/2" pressure drop at the manifold of each
appliance on the line at full rate.
Recommended supply pressures are 7" WC, (NAT), and
11" WC, (PRO); ± 5%. (Must not exceed 13.8" WC [NAT], and
15" WC [PRO]).
Electrical Connection
A 15 AMP service must be provided for each oven. For 115
VAC usage, a cord and plug (NEMA #5-15P) is provided but
connection to the electrical service must be electrically
grounded in accordance with local codes, or in the absence of
local codes, with the National Electrical Code, ANSI/NFPA 70,
or the Canadian Electrical Code, CSA C22.2, as applicable.
This appliance is equipped with a three-prong (grounding)
plug for your protection against shock hazard and should
be plugged directly into a properly grounded three-prong
receptacle.
DO NOT CUT OR REMOVE THE
CAUTION:
A wire diagram is axed to the rear of the unit.
GROUNDING PRONG FROM THIS PLUG.
DISCONNECT BOTH UNITS FROM
ELECTRICAL SUPPLY BEFORE SERVICING.
POWER FAILURE
In the event of a power failure, no attempt
should be made to operate this oven.
Part # MCOSM06 Rev 1 (11/03/08) Page 9
Ventilation & Air Supply
Proper ventilation is highly important for good operation.
There are only two choices for properly venting an oven: 1)
canopy hood style or 2) direct venting. The ideal method
of venting a GAS Convection Oven is through the use of a
properly designed canopy, which should extend 6" (150 mm),
beyond all sides of the appliance and 6'6" (1950 mm) from the
oor.
A strong exhaust fan will create a vacuum in the room. For an
DRAFT DIVERTER
exhaust system vent to work properly, exhaust and make-up
air must be balanced properly. For proper air balance contact
your local H.V.A.C. contractor.
Direct venting as described above, should be positioned
on the main top and fastened with sheet metal screws
provided. All parts described above are available from the
manufacturer.
All gas burners and pilots need sucient air to operate and
large objects should not be placed in rear and bottom of this
oven, which would obstruct the airow through the front.
INSTALLATION OF A DIRECT FLUE.
When the installation of a canopy type exhaust hood is
impossible the oven may be direct vented. Before direct
venting check your local codes on ventilation, in the absence
of local codes, refer to the National Fuel Code NFPA 54, ANSI
Z223.1 (latest revision).
If the unit is to be connected directly to a direct ue, it is
necessary that draft diverter be installed to insure proper
ventilation.
NOTE: Each oven has been factory tested and adjusted prior
to shipment. It may be necessary to further adjust the oven
as part of a proper installation. Such adjustments are the
responsibility of the installer. Adjustments are not considered
defects in material and workmanship, and they are not
covered under the original equipment warranty.
DO NOT UNDERSIZE VENT PIPE!
This can cause resistance to ow and impede good venting.
We suggest that if a horizontal run must be used it should
rise no less than 1/4" (6.25mm) for each linear foot of run, and
after a total of 180° of bends you should increase the size of
stove pipe by two (2") inches. The ue should rise 2' (60cm) to
3' (90cm) above the roof line or 2' (60cm) to 3' (90cm) above
any portion of a building within a horizontal distance of 10 (3
meters) feet.
The following diagram is only one example from the National
Fuel Gas Code Book NFPA 54, ANSI Z223.1, 7.5.3:
Page 10
Part # MCOSM06 Rev 1 (11/03/08)
Termination Less than 10 feet (3 meters) from ridge Termination More than 10 feet (3 meters) from ridge
Less than 10 feet (3 meters)
More than 10' (3 meters)
2' (60cm)
Min.
3' (90cm) Min.
3' (90cm) Min.
Testing & Lighting Instructions
1. Turn on main gas valve. Remove the lower front cover
and the service panel above the control panel. Drop the
control panel and leak test all ttings and connections
upstream from the service valve located on the redundant
combination gas valve. Should any gas leaks be detected,
turn OFF main gas valve, correct the problem and retest.
2. Open shuto valve located on the redundant combination
gas valve. Activate control panel and set to desired
temperature. The pilot and burner is now ignited by direct
spark. Check all ttings again and correct any leaks and
recheck.
Replace all service panels and covers before operation.
NOTE: All electronic ignition systems are supplied with a
redundant gas valve. Therefore, the unit is not supplied with
an external pressure regulator.
NOTE: During installation there will be air in the gas line, this
air will have to bleed o before ignition can be established.
The electronic ignition system has a ninety second lock-out
as a safety device on all units. Therefore, several attempts
may be required before pilot ignition is established, wait ve
minutes after each attempt.
FOR YOUR SAFETY: KEEP YOUR APPLIANCE AREA FREE FROM
COMBUSTIBLES.
TO CONSERVE ENERGY:
Do not waste energy by leaving controls at high temperature
settings during idle periods. Lower settings will keep
oven warm and ready for next use period. Master 400
Series controls have an auto setback feature that is user
programmable to help with these applications.
Part # MCOSM06 Rev 1 (11/03/08) Page 11
OPERATION
Master 200 Mechanical Control with Timer
In O Mode:
When the oven is o, there are no lights or indicators.
Start Up:
Press the Cook/O/Cool Down rocker switch to the "Cook"
position. The green lamp will light indicating the oven is
powered in cook mode.
The oven will begin to heat to the temperature set on the
thermostat dial. The amber lamp will light indicating the heat
is active. As the heat cycles on and o to maintain the set
temperature this light will go on and o accordingly.
The door must be closed for the oven to operate in cook
mode. Opening the door will cause the heat to stop. The
motor and fan will shut o. This is a safety feature.
Fan Speed:
The fan speed can be either high (1725 RPM) or (1150 RPM).
The fan speed is controlled by the left rocker switch marked
high and low.
Lights:
The oven lights are activated by pressing the light switch on
the control panel. This is a momentary switch and the lights
will stay lit as long as this button is held in the on position.
Lights will work whenever there is electrical power connected
to the oven.
Cool Down:
Pressing the Cook/O/Cool Down rocker switch to the Cool
Down position activates the fan and motor to cool the oven
cavity. The door must be open slightly for the fan and motor
to start. The heat is not active in this mode.
Optimal cool down will be achieved with the door open
slightly. Opening the door too far will shut the fan and motor
o. This is a patented safety feature.
Pressing the button to the OFF position cancels the cool
down and turns the oven o.
Temperature:
The temperature range is from 150°F to 500°F (66°C to 250°C)
is controlled by rotating the temperature dial and aligning the
indicator to the desired temperature.
Timer:
The timer is set by rotating the dial clockwise aligning the
indicator to the desired time cycle. The timer will count down
from 2 minutes to 60 minutes. At the end of the timing cycle
the buzzer will sound. The buzzer is turned o by rotating the
dial counter-clockwise to the o position as shown on the
control panel.
Page 12
Part # MCOSM06 Rev 1 (11/03/08)
MASTER 300 Solid State Control
with Mechanical Timer
In O Mode:
When the controller is o, the unit will have no active
prompts. Pressing the ON/OFF key will activate the controller
into Start Up mode.
On Start Up:
In Start Up mode, the controller will heat to the temperature
indicated on the temperature control. The fan speed will
be that which was most recently set. When the oven cavity
reaches the set temperature and is ready for operation the
"LOAD" LED will light.
Controller Keys
Pressing the ON/OFF key will activate the oven.
Pressing the LIGHT key will turn the lights on for 30 seconds.
The lights will work if the controller is in the O mode. When
the door is opened, the light will come on and stay on for 30
seconds.
Pressing the FAN HIGH key will activate the higher speed fan
and light its LED.
Pressing the FAN LOW key will activate the lower speed fan
and light its LED.
Pressing the COOL DOWN key will deactivate the heat, turn
the fan on high and light its LED. The Cool Down will operate
when the door is closed or opened slightly. When the door
opens wider, the Cool Down mode will deactivate and the
LED will ash. This is a patented safety feature. Optimal cool-
down will be achieved with the door open slightly. If the
doors are closed, the LED will ash. Pressing the COOL DOWN
key again will turn the LED o and stop this mode. Pressing
the ON/OFF key will also cancel Cool Down.
When the door is opened the fan and heat will stop until the
door is closed. This is a patented safety feature.
When the ON/OFF key is pressed to turn the oven o and the
oven is above 200°F (93°C), the oven will go into an Auto Cool
Down mode. In Auto Cool Down, the oven will run the fan on
high until the oven cavity drops below 150°F (66°C). During
this time the "AUTO COOL DOWN" LED will light. When the
oven temperature drops below 150°F (66°C) the oven turns
o. This feature protects the oven motor from pre-mature
failure. Optimal cool-down will be achieved with the door
open slightly. Controller Dials.
Cooking TEMPERATURE is set by rotating the TEMPERATURE
dial to the desired temperature, 150°F (66°C) to 550°F (288°C).
Cooking TIME is set by rotating the TIMER dial to the desired
cooking time, up to 60 minutes.
Part # MCOSM06 Rev 1 (11/03/08) Page 13
NOTE: The "PROBE ERROR" LED will light if the oven
temperature probe is malfunctioning or has become
damaged or disconnected. Call for service if this occurs.
MASTER 410 ELECTRONIC CONTROL
MASTER 450 ELECTRONIC CONTROL
WITH COOK-N-HOLD
MASTER 455 ELECTRONIC CONTROL WITH
COOK-N-HOLD & CORE PROBE
In O Mode:
When the controller is o, the display will show "OFF".
Pressing the ON/OFF key will activate the controller into Start
Up mode.
On Start Up:
In Start Up mode, the controller will heat to the last set
temperature, time and fan speed. The factory defaults are
350°F (177°C), 30 minutes and low fan speed. The display will
indicate "LO" when the oven is below the set temperature.
When the oven cavity reaches the set temperature and is
ready for operation the display will indicate "LOAD".
NOTE: If the oven temperature goes above the requested
temperature the display will indicate "HI". If the oven
temperature goes above 575°F (302°C) the display will
indicate "HELP" and an audible signal will sound. This is a
safety feature.
If the door is opened during a Cooking mode, the fan and
heat will stop, and the display will indicate "DOOR" until the
door is closed. This is a patented safety feature.
Pressing the ACTUAL TEMP key will display the actual oven
temperature in 5° increments. Controller Keys.
Pressing the ON/OFF key will activate the oven.
Pressing the LIGHT key will turn the lights on for 30 seconds.
The lights will work if the controller is in the O mode. When
the door is opened, the light will come on and stay on for 30
seconds.
Pressing the FAN HIGH key will activate the higher fan speed
and light its LED.
Pressing the FAN LOW key will activate the lower fan speed
and light its LED.
Pressing the FAN PULSE key will activate the lower fan speed
and light its LED. The fan will be active for 30 seconds then o
for 30 seconds, and continues this cycle.
Page 14
Part # MCOSM06 Rev 1 (11/03/08)
Pressing the SETBACK key will cool the oven cavity to a
preprogrammed temperature (factory set at 250°F [121°C]).
The oven will automatically go into Setback mode after the
pre-programmed non-usage time, (see 'Changing Factory
Setback Program'). The display will indicate "SETB". This is an
energy-saving feature.
Pressing the COOL DOWN key will deactivate the heat, turn
the fan on high and light its LED. The display will indicate
"OPEN DOOR" if the door is closed, prompting the user to
open the door slightly. With the door open slightly the display
will indicate "COOL". The Cool Down will operate when the
door is closed or opened slightly. Optimal cool-down will be
achieved with the door open slightly. When the door opens
wider, the Cool Down mode will deactivate and the display
will indicate "DOOR". This is a patented safety feature. Pressing
the COOL DOWN key again will turn the LED o and stop this
mode. Pressing the ON/OFF key will also cancel Cool Down.
Cool Down is not active during a cook.
When the ON/OFF switch is pressed to turn the oven o and
the oven was above 200°F (93°C), the oven will go into an
Auto Cool Down mode. In Auto Cool Down, the oven will
run the fan on high until the oven cavity drops below 150°F
(66°C). During this time the display will indicate "AUTO".
When the oven temperature drops below 150°F (66°C) the
oven turns o. This feature protects the oven motor from pre-
mature failure. Optimal cool-down will be achieved with the
door open slightly.
Operating the Controls
Setting the cook temperature and time are done in the same
manner. Pressing the SET key will light the TEMP LED. The
operator then sets the temperature by rotating the dial on
the controller until the desired temperature is shown on the
display. Pressing the SET key a second time lights the TIME
LED and allows the operator to select the desired cook time as
shown on the display. Pressing the SET key a third time ends
the programming.
Pressing the START/CANCEL key will start the timing cycle.
The display will count down from the Set time in minutes and
seconds (solid colon) or hours and minutes (blinking colon)
the minutes and seconds. When the cycle is completed,
processing this key will also cancel the "DONE" prompt. To
cancel a timing cycle in progress, press and hold the START/
CANCEL key for 3 seconds.
Cook-N-Hold Operation
Pressing the COOK/HOLD (450 and 455 Controllers Only) key
activates the Cook-N-Hold mode and lights its LED. To verify
the proper hold temperature has been selected, press the SET
key twice. The display will show the hold temperature. At the
end of the cook cycle, an audible alarm will sound, the display
will ash "DONE" and change to count "UP" the hold time.
The oven will switch to the programmed hold temperature.
Part # MCOSM06 Rev 1 (11/03/08) Page 15
Setting the cook temperature, hold temperature and time
are done in the same manner. Pressing the SET key will
light the TEMP LED. The operator then sets the temperature
by rotating the dial on the controller until the desired
temperature is shown on the display. Pressing the SET key a
second time will light the HOLD LED and allows the operator
to select the desired hold temperature as shown on the
display. Pressing the SET key a third time lights the TIME LED
and allows the operator to select the desired cook time as
shown on the display. Pressing the SET key a fourth time ends
the programming.
Pressing the START/CANCEL key will start the timing cycle.
When the cycle is completed, pressing this key will also cancel
the "DONE" prompt. To cancel a timing cycle in progress press
and hold the START/CANCEL key for 3 seconds.
Core Probe Operation
The Core Probe option (455 Controller Only) is only active
when the core probe is plugged into its connector. To set the
core temperature, rst plug the core probe into its connector.
The display will indicate "100" and the CORE TEMP LED will
be on. The operator then sets the temperature by rotating
the dial on the controller until the desired temperature is
shown on the display. Pressing the SET key stores the core
temperature and starts the cooking process.
To set the oven temperature, press the SET key again. The
TEMP LED will light and the oven temperature can be
set by rotating the dial on the controller until the desired
temperature is displayed. Pressing the SET key again will
light the HOLD LED allowing the operator to set the hold
temperature in the same manner.
NOTE: If the hold temperature is not set, the default hold
temperature is 150°F (66°C) or the last programmed
temperature. (Hold temperature range is 140°F (60°C) to
210°F (99°C).
When the core temperature is reached, the display will sound
and ash "DONE" for 3 seconds. Automatically, the display
will switch to count "UP" the time the oven is on hold.
CHANGING FACTORY SETBACK PROGRAM
To change the factory setback settings, press and hold the
SETBACK key for two seconds. The TEMP LED will light and
a temperature will be displayed (factory preset at 250°F
[121°C]). Set the temperature using the dial, then press the
SET key. The TEMP LED will go out and the TIME LED will light.
Set the time using the dial, then press the SET key. Press the
SET key one more time to exit programming.
Note: To disable the setback function, set the temperature to
250º F (121ºC) and the time to zero..
Page 16
Part # MCOSM06 Rev 1 (11/03/08)
MASTER 470/475 ELECTRONIC
PROGRAMMABLE CONTROL
Manual cooking:
1. Press SET key - TEMP LED will light.
2. Set temperature using the dial (factory preset at 350°F).
3. Press SET key - FAN LED will light.
4. Select fan mode using one of the three (3) fan keys
(HIGH, LOW, PULSE) - the selected fan LED will light.
5. Press SET key - TIME LED will light.
6. Set cook time using the dial (factory preset at 30:00).
7. Press SET key - ready to cook.
8. Press START/CANCEL to begin manual cooking.
Manual cooking using Cook-N-Hold:
1. Press the COOK/HOLD key, that key's LED will light.
2. Press SET key - TEMP LED will light.
3. Set cook temperature using the dial (factory preset at
350°F).
4. Press SET key - HOLD LED will light.
5. Set hold temperature using the dial (factory preset at
200°F).
6. Press SET key - FAN LED will light.
7. Select fan mode using one of the three (3) fan keys
( HIGH, LOW, PULSE ) - the selected fan LED will light.
8. Press SET key - TIME LED will light.
9. Set cook time using the dial (factory preset at 30:00).
10. Press SET key - ready to cook.
11. Press START/CANCEL to begin manual cooking.
Programming Product Keys (Master ):
NOTE: Cooking time(s) is the element of the program that tells
the controller that other information (temperature, fan
speed, etc.) will be inputted into the controller. The rst
step is to enter all the time periods required, followed by
the addition of the other cooking elements.
Part # MCOSM06 Rev 1 (11/03/08) Page 17
1. Press and hold PROG key for three (3) seconds - all the
product key LEDs light.
2. CODE will be displayed. The controller is asking for the
access code. Press 4-2-7-5 and the START/CANCEL key.
PROD will be displayed indicating you have gained access
to Product Programming.
3. Press the product key (1 - 9) into which you want to store
a cooking program. SHLF will be displayed. The control is
asking if you want to program the key as a shelf timer or
with a cooking prole. Select your answer by pressing the
START/CANCEL key. When the correct answer is displayed,
press the SET key. The TIME LED will light. 30:00 will be
displayed.
4. Set rst cook time using dial. If more than one cooking
prole is desired:
•presstheproductkeywheretheprogramistobestored
(1 - 9) - PR-2 will be displayed.
•setthesecondcooktimeusingthedial(factorypresets
for PR-2 through PR-5 are :00).
•pressthesameproductkey(1-9)again-PR-3willbe
displayed.
•Repeatthisprocessforallproles.Whenthelastprole
time has been entered, press the SET key, OR
If less than ve (5) proles are desired press the SET key
after the last required prole - PRE will be displayed,
followed by :00. The controller is asking if you would like a
reminder alarm (pre-alarm) to sound during the cooking
process. (factory preset is :00).
5. If a pre-alarm signal is desired - dial in the time that the
alarm is to sound. (Ex. If the product is to be turned
halfway through the 60 minute cooking cycle, set the
pre-alarm to 30 minutes). If pre-alarm is not desired verify
that ":00" is displayed. Press the SET key - TEMP Led will
light, and the display will show the rst prole cooking
temperature. (factory preset at 350°F).
6. Set the rst cooking temperature using the dial.
Press the product key - PR-2 will be displayed followed by
the second temperature.
Set the second cooking time using the dial.
Repeat as you did for cooking time, for all the proles
desired.
NOTE: The controller will only accept cooking temperatures
for the number of proles for which a cooking time
has been set. If the product key is pressed after the
last programmed prole, the rst temperature will be
displayed.
Page 18
Part # MCOSM06 Rev 1 (11/03/08)
Press SET after the last cooking temperatures has been
entered, HOLD will be displayed.
7. Use the START/CANCEL key to select yes or no. Press the
SET key.
4. If a pre-alarm signal is desired - dial in the time that
the alarm is to sound. (Ex. If the product is to be turned
halfway through the 60 minute cooking cycle, set the prealarm to 30 minutes). If pre-alarm is not desired verify that
":00" is displayed.
8. If yes was selected, the HOLD LED will light. Enter the hold
temperature using the dial. (factory preset at 200°F) Press
the SET key. FAN will be displayed and the FAN LED will
light.
Set the fan speed desired for the rst cooking prole using
the individual fan keys (HIGH, LOW or PULSE), press the
product key and set the fan speed for the second cooking
prole. Continue until all the proles have been assigned
a fan speed. Press the SET key when complete. As with the
temperature, if the product key is pressed after the last
programmed prole, the rst fan speed will be displayed.
9. FL or St will be displayed (for ex time or straight time)
(factory preset for ex time). Select ex or straight time
using the START/CANCEL key for the rst prole. Press
the product key and select straight time or ex time for
the second prole. Continue until all the proles have
been assigned straight or ex time. Press the SET key
when complete. If the product key is pressed after the last
programmed prole, the rst prole will be displayed.
10. Programming for that product key is complete.
Programming Product Keys (Master ):
•PresstheSETkey-TEMPLedwilllight,andthedisplay
will show the cooking temperature. (factory preset at
350°F).
5. Set the cooking temperature using the dial.
Press the SET key. - FAN will be displayed and the FAN LED
will light.
6. Set the fan speed desired using the individual fan keys
(HIGH, LOW or PULSE).
Press the SET key. - FL or St will be displayed (for ex time
or straight time) (factory preset for ex time).
7. Select ex or straight time using the START/CANCEL key.
Press the SET key when complete.
8. Programming for that product key is complete.
Cooking Using The Product Keys
(Master and Master ):
1. On initial start-up, press the product key for the menu
item to be cooked. Wait until LOAD is displayed.
NOTE: The Master 470 controller will only accept a single
cooking prole per product key (one cooking time, one
cook temperature, one fan speed, and one choice for
straight or ex time).
Press and hold PROG key for three (3) seconds - all the
product key LEDs light.
1. CODE will be displayed. The controller is asking for the
access code. Press 4-2-7-5 and the START/CANCEL key.
PROD will be displayed indicating you have gained access
to Product Programming.
2. Press the product key (1 - 9) into which you want to store
a cooking program. SHLF will be displayed. The control
is asking if you want to program the key as a shelf timer
or a cooking prole. Select your answer by pressing the
START/CANCEL key. When the correct answer is displayed,
press the SET key. The TIME LED will light. 30:00 will be
displayed.
3. Set the cook time using dial.
Press the SET key - PRE will be displayed, followed by :00.
The controller is asking if you would like a reminder alarm
(pre-alarm) to sound during the cooking process. (factory
preset is :00).
2. Load the oven.
3. Press the product key for the loaded menu item.
4. Press the START/CANCEL key.
5. To cancel the alarm or the hold, press the START/CANCEL
key followed by the product key.
Verifying hold time (Master and Master ):
While a product is being held, press and hold the product
key. The actual hold time will be displayed.
Selecting Fahrenheit or Celsius (Master 475 and Master
470):
Press PROG and ACTUAL TEMP keys at the same time, F or
C will be displayed. (factory preset for F)
Press the START/CANCEL key to switch between F and C,
When the desired setting is displayed press the PROG and
ACTUAL TEMP keys at the same time.
Part # MCOSM06 Rev 1 (11/03/08) Page 19
Cooking with the Shelf Timer
(Master and Master ):
The shelf timer option is used to independently time each of
the up to six dierent shelves or racks within the oven.
NOTE: To use the shelf timer option, at least one product
key must be programmed with a cooking prole
(temperature, time, fan speed, ex or straight time). The
program key must be limited to a single cooking prole
to be used with the shelf timing option. If more than one
product key is to be used, all product keys to be used must
feature the same cooking temperature and fan speed. Flex
or straight time and cooking time can de dierent. The
Cook-N-Hold option can not be used with the shelf timer
operation.
Example: Two product proles contain the same cooking
temperature, fan speed and are both programmed for ex
time - keys 1 and 6.
Two trays of product are going to be cooked in the oven at
the same time. The rst tray will use product key 1 and will be
placed in rack position 2. The second tray will use product key
6 and will be placed in rack position 4. Once the oven display
indicates LOAD:
1. Load food product into oven on shelf 2.
2. Press product key 1, then shelf key 2.
3. Press the START/CANCEL key to start cooking on shelf 2.
4. Load food product into oven on shelf 4.
Pressing the desired product key will bring the oven to the
desired cooking temperature, once the oven has reached
the proper cooking temperature as indicated by LOAD in the
display.
1. Press the product key containing the desired cooking
prole (1 - 9).
2. Press the shelf key for the shelf location to be timed (1 - 6).
NOTE: product keys and shelf keys are the same keys.
3. Press the START/CANCEL key to begin the cooking/timing
process.
4. When the cooking/timing process is complete for each
shelf, an audible "done" signal will sound and the display
will indicate which shelf is nished. Example: SH-1
5. To turn o the alarm press the product key with the
ashing LED.
5. Press product key 6, then shelf key 4.
6. Press the START/CANCEL key to start cooking on shelf 4.
7. When product on shelf 2 is nished cooking, an audible
alarm will sound and the display will ash DONE, then
SH-2, and the product key 1 LED will be ashing.
8. To turn o the alarm, press product key 1.
9. When product on shelf 4 is nished cooking, an audible
alarm will sound and the display will ash DONE, then
SH-4, and the product key 6 LED will be ashing.
10. To turn o the alarm, press product key 6.
Page 20
Part # MCOSM06 Rev 1 (11/03/08)
PERFORMANCE RECOMMENDATIONS
1. Preheat oven thoroughly (approximately. 20 minutes)
before use.
2. As a general rule, temperature should be reduced 25°
to 50° from that used in a standard/conventional oven.
Cooking time may also be shorter, so we suggest closely
checking the rst batch of each product prepared.
3. Use the chart of suggested times and temperatures as a
guide. These will vary depending upon such factors as size
of load, temperature and mixture of product (particularly
moisture) and density of product.
4. Keep a record of the times, temperature and load sizes you
establish for various products. Once you have determined
these, they will be similar for succeeding loads.
5. When practical, start cooking the lowest temperature
product rst and gradually work up to higher
temperatures.
6. If you nd that your previous temperature setting is more
that 10° higher than needed for succeeding loads, press
the COOL DOWN key to reach the desired temperature
before setting a new cooking temperature.
7. When loading oven, work as quickly as possible to prevent
loss of heat.
10. When baking, weigh or measure the product in each pan
to assure even cooking.
11. When cooking six pans, use rack positions 2, 4, 6, 8, 10 and
12, starting from the top.
12. Do not overload the oven. Six pans are suggested for most
items, i.e., cakes, cookies, rolls, etc. However, the maximum
(13 pans) may be used for sh sticks, chicken nuggets and
hamburgers. Cooking times will have to be adjusted.
13. Mun pans should be placed in the oven back to front or
with the short side of the pans facing the front. This results
in the most evenly baked product.
14. When re-thermalizing frozen casseroles, preheat the oven
100° over the suggested temperature. Return to cooking
temperature when the oven is loaded. This will help
compensate for the introduction of a large frozen mass
into the cavity.
15. Use pan extenders or two inch deep 18"x26" pans for
batter type products which weigh more than eight
pounds, i.e., Pineapple Upside Down Cake.
16. Never place anything directly on the bottom of the oven
cavity. This obstructs the airow and will cause uneven
results.
8. Oven will continue to heat even though the timer goes
o. Product should be removed from the oven as soon as
possible to avoid over cooking.
9. Center pans on racks and load each shelf evenly to allow
for proper air circulation within the cavity.
NOTE: Moisture will escape around the doors when baking
products with heavy moisture content, such as: chicken,
potatoes, etc.
Part # MCOSM06 Rev 1 (11/03/08) Page 21
COOKING GUIDE
The following suggested times and temperatures are provided as a starting guide. Elevation, atmospheric conditions, gas
supply, recipe, cooking pans and oven loading may aect your actual results.
Product °F Time
White Sheet Cakes – 5 lb 300° 20 min
White Sheet Cakes – 6 lb 300°
Yellow Layer Cake – 21 oz 325° 15 min
Yellow Sheet Cake – 5 lb 300° 22 min
Chocolate Layer Cake – 21 oz 300° 22 min
Angel Food Cake 375° 22 min
Brownies 350° 15 min
Product °F Time
Chicken Parts 350° 45 min
Hamburger Patties, 10/lb fzn 350° 8 min
Hamburger Patties, 10/lb fresh 350° 5 min
Hamburger Patties, 4/lb fzn 350° 12 min
Hamburger Patties, 4/lb fresh 350° 8 min
Meatloaf – 4# 325° 45 min
Bacon 350° 10 min
Roast Beef - 20# 325° 3 hr 15 min
Prime Rib - 10# 300° 1 hr 45 min
Stued Pork Chops 350° 45 min
Lamb Chops 375° 40 min
Boneless Veal Roast 300° 3 Hr
Product °F Time
Soda Biscuits 400° 6 min
Yeast Rolls 325° 24 min
Sweet Bread 325° 24 min
Corn Bread 350° 22 min
Gingerbread 300° 24 min
Apple Turnovers 350° 25 min
Cream Pus 300° 25 min
Sugar Cookies 325° 12 min
Chocolate Chip Cookies 375° 8 min
Apple Pie (Fresh) 375° 25 min
Blueberry Pie (Fresh) 350° 30 min
Blueberry Pie (Frozen) 300° 56 min
Pumpkin Pie (Frozen) 300° 50 min
Frozen Pizza 300° 6 min
Macaroni & Cheese 350° 15 min
Fish Sticks 350° 16 min
Stued Peppers 350° 45 min
Baked Potatoes 350° 60 min
Page 22
Product °F Time Product °F Time
Part # MCOSM06 Rev 1 (11/03/08)
COOK AND HOLD
Please refer to the operating instructions to program the 450 and 455 control units for cook and hold feature. The times and
temperatures listed below are to be used as a starting guide. Your actual results may vary greatly depending on your elevation,
gas supply, atmospheric conditions and other items being cooked at the same time.
Time in Hours
Weight in
lbs
8 2.5 3.5 1.5 2 1.25 1.5
9 2.75 3.75 1.75 2.25 1.25 1.75
10 3 4.25 2 2.5 1.5 1.75
11 3.25 4.5 2 2.75 1.5 1.75
12 3.5 5 2.25 3 1.5 2
13 3.75 5 2.5 3.25 1.5 2.25
14 4 5.75 2.5 3.5 1.75 2.5
15 4.25 6 2.75 3.5 2 2.5
16 4.5 6.25 2.75 3.75 2 2.75
17 4.75 6.5 3 4 2.25 2.75
18 4.75 6.75 3.25 4.25 2.25 3
19 5 7.25 3.25 4.25 2.25 3
20 5.25 7.5 3.5 4.5 2.5 3.25
21 5.5 7.75 3.5 4.75 2.75 3.5
22 5.75 7.75 3.5 4.75 2.75 3.5
23 6 8.25 3.75 5 2.75 3.75
24 6 8.75 3.75 5 2.75 3.75
25 6.25 9 4.25
26 6.5 9.25 4.25 5.5 3.25 4.25
27 6.75 9.5 4.25 5.75 3.25 4.25
28 7 9.75 4.5 6 3.25 4.25
29 7.25 10 4.75 6.25 3.5 4.5
30 7.25 10.25 4.75 6.25 3.5 4.5
Temperature: 200°F Temperature: 250°F Temperature: 300°F
Rare Medium Rare Medium Rare Medium
5.5 3 4
Part # MCOSM06 Rev 1 (11/03/08) Page 23
PROBLEMS / SOLUTIONS
Problem Solution
If cakes are dark on the sides and not done in the center Lower oven temperature.
If cakes edges are too brown Reduce number of pans or lower oven temperature.
If cakes have light outer color Raise temperature.
If cake settles slightly in the center
If cake ripples Overloading pans or batter is too thin.
If cakes are too coarse Lower oven temperature.
If pies have uneven color Reduce number of pies per rack or eliminate use of bake pans.
If cupcakes crack on top Lower oven temperature.
If meats are browned and not done in center Lower temperature and roast longer.
If meats are well done and browned Reduce time. Limit amount of moisture.
If meats develop hard crust Reduce temperature or place pan of water in oven.
If rolls have uneven color Reduce number or size of pans.
Bake longer or raise oven temperature slightly.
Do not open doors too often or for long periods.
Page 24
Part # MCOSM06 Rev 1 (11/03/08)
CLEANING & MAINTENANCE
NOTE: Disconnect line cord from power supply before
cleaning or servicing.
Break-In Period
When oven is new, operate it for one hour at 450°F before you
begin your normal cooking operation. After cooling, wipe the
interior, including the racks, with a clean damp cloth.
Exterior Cleaning
Establish a regular schedule. Any spills should be wiped o
immediately.
1. The oven should always be allowed to cool suciently
before any cleaning is attempted.
2. Wipe exposed, cleanable surface when cool with a mild
detergent and hot water. Stubborn residue spots may be
removed with a lightweight non-metallic scouring pad.
Dry thoroughly with a clean cloth.
3. Painted surfaces should be cleaned using a mild soap
and warm water solution on a sponge or soft Cloth. Dry
thoroughly.
4. Stainless Steel surfaces can often be cleaned adequately
with the same method. Stubborn stains may be removed
by using a non-metallic abrasive pad, rubbing in the
direction of the metal's grain. If necessary, for particularly
heavy deposits, you may mix a thin paste of water and
scouring powder, and apply it with a sponge. Be careful
to apply light pressure and remember to rub only in the
direction of the grain in the metal.
5. The control panel surface is easily cleaned with hot water,
soap and a soft cloth. Do not use hard abrasives, solvent
type materials or metallic scouring pads since these will
scratch or cloud the surface.
6. Never spray the perforated areas or control panel with
steam or water, as this will allow moisture into the control
cavity, which could damage electrical components.
Interior Cleaning
Establish a regular cleaning schedule or wipe o on the same
day when spillovers occur.
1. Cool down oven.
2. Remove oven racks.
3. Lift rack guides on either side of oven o of holders. Racks
and guides may be run through dishwasher while oven
cavity is being cleaned.
4. Clean with soap and water using a non-metallic scouring
pad, if necessary. If dirt and grease have accumulated, a
mild ammonia solution or commercial oven cleaner such
as Easy-O or Dow may be used.
5. To reinstall, reverse procedure. Place the bottom of the
rack guide against the cavity wall. Keeping the top pulled
away from the wall lift up. Push the top of the rack guide
against the wall and push down locking it into place.
Fan Area Maintenance
If aluminum foil is routinely used to wrap food or cooking
vessels during oven operation, the following preventive
maintenance must be performed:
1. Turn power switch to "OFF" position.
2. Remove oven racks and rack guides.
3. Remove air bae and clean any stains or deposits.
4. Check blower wheel and air bae for particles of
aluminum foil or food deposits. Clean ns of blower
wheel. (Caution: edges of blower wheel ns may be
sharp).
5. Reinstall the air bae, rack guides and oven racks.
This simple practice, if performed on a regular basis will
keep your Garland oven operating at peak performance.
Part # MCOSM06 Rev 1 (11/03/08) Page 25
MOTOR CARE
The motor on your convection oven is maintenance free since
it is constructed with self-lubricating sealed ball bearings.
It is designed to provide durable service when treated with
ordinary care. We have a few suggestions to follow on the
care of your motor. When the motor is operating, it cools
itself internally by air entering at the rear of the motor case,
provided proper clearance has been allowed.
Since the blower wheel is in the oven cavity it is at the same
temperature as the oven. If the motor is stopped while the
oven is hot, the heat from the blower wheel is conducted
down the shaft and into the armature of the motor. This
action could shorten the life of the motor.
We recommend, at the end of the bake or roasting period,
when the oven will be idle for any period of time, or before
shutting down completely, that the doors be left open
slightly, and press the COOL DOWN key on the control panel.
The fan will continue to run until the oven cools down to
150°F (66°C). At the end of the day, press the ON/OFF key to
activate the Auto Cool Down feature. The fan will run on high
until the oven cavity drops below 150°F (66°C). During this
time the "AUTO COOL DOWN" LED will light. When the oven
temperature drops below 150°F (66°C) the oven turns o.
This feature protects the oven motor from pre-mature failure.
Optimal cool-down will be achieved with the door open
slightly.
Page 26
Part # MCOSM06 Rev 1 (11/03/08)
Section Two
Electronic Pilot
& Main Burner
Part # MCOSM06 Rev 1 (11/03/08) Page 27
IGNITION SEQUENCE
START
STAGE 1
TRIAL FOR
IGNITION
STAGE 2
MAIN BURNER
OPERATION
END
1. CONTROLLER CALLS FOR HEAT
2. SPARK GENERAT OR POWERED
First valve (Pilot) operator opens
3. PILOT BURNER OPERATION
Pilot burner lights.
Module senses
ame current.
OR Pilot burner does not light.
After 90 seconds system
locks out: must be
manually reset.
4. FLAME CURRENT SENSED
•
Spark generator o.
• Second valve operation (main) opens
POWER INTERRUPTION
System shuts o, restarts
when power is restored
PILOT FLAME FAILURE
Main valve closed.
Module start trail for ignition.
5. MAIN BURNER OPERATION
Module monitors pilot ame current
6. CONTROLLER SATISFIED
Valves close, pilot and main burners are o
First Stage – Trial For Pilot Ignition
On every call for heat (system start), the S86 performs an
internal safe-start check and shows that a ame-simulating
condition is present. During a normal start, the S86 opens the
pilot valve in the gas control. This allows gas to ow to the
pilot burner. Simultaneously the electronic spark generator
in the S86 produces a 30,000 volt pulse output. This voltage
produces a spark at the pilot burner igniter/sensor rod,
igniting the gas ow around the electrode. If the pilot ame
is not detected during the trial for pilot ignition, the S86H
contains a safety lockout timer (90 Seconds) to limit the
ignition period.
Second Stage – Main Burner Operation
When the Pilot ame is established, a ame rectication
circuit is complete to the burner ground. The S86 ame
sensing circuit detects the ame circuit and shuts the spark
generator o. At the same time the second operator (main
gas valve) is opened in the gas control, allowing gas ow
to the burners. This pilot ame ignites the main burner
conventionally.
Safety Lock Out Time.
The safety lockout timer circuit starts timing the moment the
trail for the pilot ignition starts. When the timing periods runs
out, the trial for ignition ends, and the control module goes
into lockout. Before another attempt to start can be made,
the S86 must be reset. Reset by adjusting the thermostat or
controller below room temperature, or to its "OFF" position.
An alternate method is to shut the system power "OFF". If
normal ignition does not occur, use the trouble shooting
table to determine the problem.
Page 28
Part # MCOSM06 Rev 1 (11/03/08)
NO
NO
NO
NO
NO
NO
NO
NO
START
YES
YES
YES
YES
YES
YES
YES
YES
TROUBLE SHOOTING TABLE
TURN GAS SUPPLY OFF.
TURN CONTROLLER TO
CALL FOR HEAT POWER
TO MODULE
(24V NOMINAL)
SPARK ACROSS IGNITER/
SENSOR GAP
TURN GAS SUPPLY ON
PILOT BURNER LIGHTS?
Check line voltage power, low voltage transformer, limit controlled and wiring.
Pull ignition lead
and check spark and
module.
Spark okay?
• Checkignitioncable,groundwire,ceramicinsulatorandgapandcorrect.
• Checkbootoftheignitioncableforsignsofmeltingorbuckling.Takeprotectiveactiontoshield
cable and boot from excess temperature.
• Checkthatallmanualgasvalvesareopen,supplytubingandpressurearegood,andpilotburner
orice is not blocked.
• Checkelectricconnectionsbetweenmoduleandpilotoperatorongascontrol.
• Checkfor24VACacrossPV-MV/PVterminalsonmodule.Ifvoltageisokay,replacegascontrol;if
not, replace module.
Note: Before trouble shooting familiarize yourself with
the startup procedure.
•Onmodels with ventdamperplug,makesure ventdamper
had not be installed, the remove. Replace vent damper if
necessa ry.
•Onothermodels,replacemodule
SPARK STOPS WHEN
PILOT IS LIT?
MAIN BURNER LIGHTS?
SYSTEM RUNS UNTIL
CALL FOR HEAT LOSS?
CALL FOR HEAT ENDS
SYSTEM SHUTS OFF?
TROUBLE SHOOTING
ENDS
Note: If S5800B, H; S6810B, H goes into lockout, reset system. For S6800M, wait 6 minutes nominal
for retry or reset system
• Checkcontinuityofignitioncabletogroundwire.
• Cleanamerod.
• Checkelectricalconnectionbetweenamerodandmodule.
• Checkforcrackedceramicamerodinsulator.
• Checkthatthepilotamecoverstheroadandissteadyandblue.
• Adjustpilotame.
• Ifproblempersists,replacemodule.
• Checkfor24VACacrossMV-MV\PVterminals.Ifnovoltage,replacemodule.
• Checkelectricalconnectionsbetweenmoduleandgascontrol.Ifokay,replacegascontrolorgas
control operator.
Note: If S8600B, H; S6810B, H goes into lockout, reset system. For S6800M, wait 6 minutes, nominally
for retry or reset system.
• Checkcontinuityofignitioncableandgroundwire.
Note. If ground is poor or erratic, shutdowns may occur occasionally even though operation is
normal at the time of checkout.
• Checkthatthepilotamecoversamerodandissteadyandblue.
• Ifchecksareokay,replacethemodule.
• Checkforpropercontrolleroperation
• RemoveMVleadatmodule;ifvalvecloses,recheckthetemperaturecontrollerandwiring;ifnot,
replace gas control.
Repeat procedure until trouble free operation is obtained.
Part # MCOSM06 Rev 1 (11/03/08) Page 29
SERVICE
Preliminary Check
The following visual checks should be made before trouble
shooting and after installation or maintenance.
1. Check power to the appliance and S86.
2. Manual shuto cocks in the gas line must be open.
3. Make certain all wiring connections are clean and tight.
4. First de-energize the system and wait at least one (1)
minute. This resets the module allowing a return to the
start condition.
5. Review the S86 system normal sequence of operation.
System Trouble Shooting
Start the system by setting the controller above the required
temperature. Observe the system response. Establish the type
of malfunction or deviation from the normal operation. Use
the S286 Intermittent Pilot system trouble shooting table to
check for normal system operation.
Use the table by following the instruction questions in the
box. If the conditions is true or okay (answers yes), go down
to the next box underneath. If the condition is not true of
not okay (answer no), go right to the next box alongside.
Continue checking and answering conditions in each box
encountered, until a problem and/or the repair is explained.
After any maintenance or repair, the trouble shooting
sequence should be repeated until the trouble shooting
procedure ends with a normal system operation.
Check Grounding
Electric grounding connections at the pilot burner,
igniter/sensor and S86 must be clean and tight. If a lead
wire is damaged or deteriorated, use only No. 14 or 18
gauge moisture resistant thermoplastic insulated wire
with 105°C (221°F) minimum ratings as replacement.
Excessive temperature at the ceramic ame rod can also
permit electrical leak to ground. Examine the ame rod and
mounting bracket, and correct if bent out of position. Replace
igniter/sensor if insulator is cracked.
Check Spark Ignition Circuit
The electronic module and step-up transformer in the S86
provides a spark ignition at 30,000 volts (open circuit). This
circuit can be checked at the S86 module as follows:
1. Turn o the manual gas cock to prevent the ow of gas.
2. Disconnect the ignition cable at the S86 stud terminal to
isolate the circuit from the pilot burner/igniter/sensor, and
prepare a shot jumper lead using heavily insulated wire,
such as ignition cable.
3. Energize the S86 touch one of the jumper rmly to the S86
ground terminal (GND). Do not disconnect the existing
ground lead. Move the free end slowly toward the stud
terminal to establish a spark and then pull the lead wire
slowly away from the stud. Not the length of the gap at
which the arching stops.
CAUTION: Do not touch either the stripped end of the jumper
or stud terminal. This is a very high voltage circuit and
electrical shock can result. Perform the test immediately upon
energizing the system – before the S86H goes into safety lock
out and interrupts the spark circuit.
A common ground is required for the pilot burner, the
igniter-sensor, the GND terminal of the S86, and the main
burner. The main burner generally serves as the common
ground. If the ground it poor or erratic, safety shutdowns may
occur occasionally even though operation is normal at time
of check out. Therefore, if nuisance shutdowns have been
reported, be sure to check the grounding.
Note: If the ground circuit path is incomplete, the S86H
system control will allow one trial for ignition before going
into safety lock out.
Page 30
4. An arch length of 1/8" (3.2mm) or more indicates a
satisfactory voltage output. Replace the S86 if not arc
can be established or the maximum gap is less then 1/8"
(3.2mm), and the fuse and power to the S86 input terminal
was okay.
Part # MCOSM06 Rev 1 (11/03/08)
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