Giersch GG20-LN, Technical Information And Installation Instructions, Page: 25 / 30

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26. Troubleshooting
Defect determined:
Flash code DMG
972
Cause: Remedy:
Burner motor does not
start up - Electric supply lead faulty Rectify faults in electrical installation
- Fuse faulty Replace
- Safety thermostat locked out Unlock
- Temperature of controller set-
ting is exceeded Renewed start attempt after tempera-
ture drop
- Control box faulty Replace
- Leak Rectify leak
- No gas Safeguard gas supply
- Gas pressure monitor faulty Replace gas train
- Filter in gas train dirty Clean or replace
Burner motor faulty Replace
- No load at terminal 5 Check plug connection and current
path of solenoid valve
Mains voltage < 187 V Rectify faults in electrical
installation
Burner starts up and
switches to fault mode
before or after expiry of
safety period Ionisation signal Solenoid valve leaking
Air pressure switch does not
switch through during pre-venti-
lation See Page 21
Ionisation monitoring device
affects ignition See Page 21
Gas solenoid valve does not
open Replace gas train
Starting gas flow set too low Increase starting gas flow
No ignition Check ignition electrode and setting,
ignition transformer and cable
(see Page 11)
Phase and zero mixed up Connect connector unit in correct
phase sequence
Ionisation monitoring device
faulty Check according to Page 21
Air pressure switch switches
during operation See Page 21
Gas nozzle dirty or faulty Replace gas nozzle
Flame extinguishes
during operation - No gas Safeguard gas supply
- Filter in gas train dirty Clean or replace
Flame blow-off Wrong burner setting
(see Pages 13-14)
Air pressure switch contact
opens Check/replace air pressure switch
(see Page 21)
Flame signal too weak Measure the flame signal, check the
ionisation electrode
(see Page 21)
Burner motor starts up
briefly. Control unit
switches to fault mode Any failure flash code Control unit was not reset Reset control unit fault
Air pressure switch not in idle
position Check air pressure controller
Control box resets auto-
matically Intermittent fault
(10 sec.) Gas pressure monitor
cause brief (1-5 sec.) gas pres-
sure fluctuations Ensure that the gas supply is intact
and set the gas pressure switch and
*a lower start point if necessary
Service instructions/dimensions