Electronic Pilot & Main Burner Ignition Sequence; First Stage - Trial For Pilot Ignition; Second Stage - Main Burner Operation; Safety Lockout Time - Garland MCO-GD-10M Service Manual

UPO - User Preference Offset. Used by the user to adjust the controlling temperature +/- 50º in 1º
increments.
1. Set the time digits to 00:00.
2. Set the temperature digits to X10º.
3. Depress & hold the Start button for five seconds.
4. "UPO" & Current UPO will be displayed. Turn TEMP or TIME dial to adjust.
TO CHANGE FAHRENHEIT TO CELSIUS (and vise versa)
1. Set the time digits to 00:00.
2. Set the temperature digits to X20º.
3. Depress & hold the Start button for five seconds.
4. Rotate either dial to display FFF or CCC in the temperature display
TIMER RESOLUTION CHANGING
1. Set the time digits to 00:00.
2. Set the cook temp to X30º
3. Depress & hold the Start button for five seconds.
4. Rotate either dial to display "HR" or "MN".
CHANGE THE HERTZ
1. Set the time digits to 00:00.
2. Set the cook temp to X40º
3. Depress & hold the Start button for five seconds.
4. Rotate either dial to display "50" or "60" Hz.
CHAIN PROGRAMMING
1. Press Pgm Mode on/off.
2. Select Pgm # (1-5).
3. Enter Event 1 parameters (time, temp, fan speed etc.). Press Event # key to
nd
chain 2 event.
4. Enter Event 2 parameters.
5. Continue procedure up to six events.
ELECTRONIC PILOT & MAIN BURNER IGNITION SEQUENCE

FIRST STAGE - TRIAL FOR PILOT IGNITION

On every call for heat (system start), the S86 performs an internal safe-start check shows that a flame-simulating
condition is present. During a normal start, the S86 opens the pilot valve in the gas control. This allows gas to flow to
the pilot burner. Simultaneously, the electronic spark generator in the S86 produces a 15,000 volt spark pulse output.
This voltage produces a spark at the pilot burner ignitor/sensor rod, igniting the gas flowing around the electrode. If
the pilot flame is not detected during the trial for pilot ignition, the S86H contains a safety lockout timer (90 Seconds) to
limit the trial for pilot ignition period.

SECOND STAGE - MAIN BURNER OPERATION

When the pilot flame is established, a flame rectification circuit is completed to the burner ground. The S86 flame
sensing circuit detects the flame current and shuts the spark generator off. At the same time, the second operator
(main gas valve) is opened in the gas control, allowing gas flow to the main burners. The pilot flame ignites the main
burner conventionally.

SAFETY LOCKOUT TIME

Entry
12
Exit
1. Depress the
Actual Temp
button to lock-in.
1. Depress the
Actual Temp
button to lock-in.
1. Depress the
Actual Temp
button to lock-in.
1. Depress the
Cancel button to
lock-in.
1. Press Pgm
Mode on/off to
exit program
mode.