Giersch GG20-LN, Technical Information And Installation Instructions

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13.Control unit DMG 972
Function testing the control unit
Danger of fatal injury from electric shocks!
Disconnect electrical cable from power supply before car-
rying out any work on live parts!
Troubleshooting may only be carried out by authorised
and trained personnel!
Unlocking may only be carried out by an authorised spe-
cialist.
Check air pressure monitor contact: device goes into fault mode when silicone connecting hose is de-
tached. Reconnect the hose to coupling
"+"
.
Bypass air pressure monitor before start-up: burner motor starts for approx. 2-3 seconds, followed by fault
shut-down. After 10 seconds, an intermittent fault is output and then automatically
reset. A second start-up attempt is made. If the air pressure switch contact is still closed, a true fault shut-
down will occur. If the air pressure switch opens the contact within 10 sec., the burner will go into operation.
Safety and switching functions
In the event of a flame failure during operation, the fuel supply is immediately switched off and the control
box goes into fault mode within 1 sec. Since the faults are not reset after a power failure, the burner motor
switches on for approx. 2-3 sec. when the supply voltage is connected before the device goes into fault
mode again and displays the last fault that occurred.
If a flame signal is given during the pre-ventilation phase, a failure shut-down will occur immediately.
The position of the air pressure controller is continuously checked. There can be no start-up if it is not in its
neutral position. If the NO contact does not close or reopens during the pre-ventilation phase, a failure shut-
down will occur. If there is an insufficient supply of air during operation, the air pressure controller contact
opens and the valves close immediately. The device switches to fault mode within 1 sec.
Fault cause diagnosis
In the event of a fault, the LED remains continuously lit. Every 10 seconds this is interrupted and a flash
code is signalled to provide information about the fault. This results in the following sequence, which re-
peats itself continually until the fault is acknowledged, i.e. the appliance is reset.
Following sequence:
Reader for failure code display:
SatroPen
Art. No. 47-10-22542
SatroCom Art. No. 47-10-22563
Luminous phase
Dark phase
lasting 10 secs.
lasting 0.6 sec.
Dark phase
lasting 1.2 secs.
Flash code
Function