Groth 8391B - Manual (Page 5)

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SAFETY PRECAUTIONS:
1. When burner is operating, all personnel should maintain a safe distance from the unit.
2. The ignition electrode provides a HIGH VOLTAGE DISCHARGE which can cause severe bodily injury or
death. DO NOT attempt to service the electrode without first disconnecting and locking out the power
supply to the control panel and transformer box.
3. All components on the main burner can be VERY HOT; DO NOT attempt to service any part of the
ignition system or pilot assembly until it has cooled. Failure to observe this precaution can cause
severe burns.
4. DO NOT SMOKE or use any equipment that could spark while working in the vicinity of the main burner.
5. ALWAYS shut off the gas supply to both the main burner and pilot line before attempting to do any
repairs on the system.
6. DO NOT remove or modify the flame check at the pilot gas supply port of the burner, drawing C-84652,
page 17.
7. Wiring of the burner must be done according to both National Electric Code and all relevant state and
local codes.
OPERATING INSTRUCTION:
The pilot operation is controlled by a MANUAL/OFF/AUTO switch. When the control switch is in the MANUAL
position, the pilot control sequence is initiated instantly, and the pilot is ignited and maintained. When the
AUTOMATIC position is selected, the pilot control functions on demand and is controlled by a remote switch. A
pressure switch is typically provided unless specified otherwise.
Manual: When the "MANUAL" position is selected, pilot fuel is turned on and the ignition electrode begins sparking.
The ignition cycle consists of 10 seconds on and 3 seconds off, with pilot fuel remaining on throughout the
cycle.
The ignition cycle is repeated until a pilot flame is established. The pilot flame is maintained regardless of
flow to the waste gas burner. The ‘Pilot Gas On’ and ‘Pilot Flame On’ lights will verify a successful pilot
flame.
Automatic: When the "AUTO" position is selected, the pilot control sequence will begin when the remote switch is
closed. Normally this is a pressure switch which is installed in the main burner supply line, upstream of the
back pressure regulator. It should be set approximately 0.5" - 1" WC below the regulator setting to ensure
that the pilot flame will be ignited before gas flows to the main burner. The pilot control is the same as in the
manual mode. The burner will continue to operate until the switch condition is interrupted.
Note: The pilot control will respond to the actual supply of waste gas. When the gas pressure drops [due to
increased consumption or decreased production], the pressure switch will open and shut off the pilot control.
The burner will stay in a "stand-by" mode until gas pressure rises and the pressure switch contact closes
which resumes the pilot control sequence.
Options: The Groth Waste Gas Burner has several options from the factory. Please contact the factory for
ordering information. The following is a short description of commonly requested options:
Bio-Gas Soleniod Valve: This option is physically connected to a Groth Model 8400A Pressure Relief and
Flame Trap Assembly and function is controlled by the Groth Waste Gas Burner Control Panel. The
Bio-Gas Solenoid Valve keeps the Model 8400A closed as to not vent bio-gas until the thermocouple
senses a proper pilot flame.
Dual Thermocouple (Waste Gas Sensing): A dual thermocouple setup on the Groth Waste Gas Burner
provides the ability to sense the pilot flame and the bio-gas flame. The advantage of sensing the bio-
gas flame is that when verified, the Control Panel will shut off the pilot gas saving the factory money
spent on maintaining a pilot flame via natural gas, propane, etc.
Temperature Controls: The thermocouple [T/C] is in direct contact with the deflector plate. The PILOT T/C
OK indicator comes on when the "sensed" temperature exceeds the T/C relay lower switch point
[ambient temperature]. This verifies that both thermocouple and monitor are functioning. When the
temperature exceeds the T/C relay upper switch point [approx. 800° F.], the PILOT FLAME ON
indicator comes on, the ignition cycle is stopped and the pilot continues to burn.