Buderus GC144/3, Инструкция по установке и обслуживанию

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15
Boiler inspection and maintenance
Logano GC 144 II – 6 720 808 893 (2017/02) 27
15.8 Troubleshooting the GC 144 II
Equipment required: Wiring diagrams (

chapter 17, page 30) and
voltage detectors for 120 VAC and 24 VAC.
Fig. 41 Troubleshooting the GC 144 II
S tart
Close gas valve. Set thermostat
(control) to require heat (vent
damper open).
Switch on power.
Observe ignition sparks in gap
between electrode and sensor
through sight glass.
• Check electrical power source, low-voltage transformer, thermostat (con-
trol) and wiring. Check that the vent damper (if installed) is open and the
limit switch is present.
No
No
No
Open main gas valve. Ignition
flame is burning.
•
Check that all manually operated baffles are open; check that gas con-
nections and pressures are correct and that ignition gas nozzles are not
blocked.
• Check electrical connection between automatic ignition and ignition timer
on the gas fitting.
• If the voltage is correct replace gas fitting, otherwise replace automatic ig-
nition.
No
System operates until the heat
requirement ends.
• Check ignition wiring and ground for continuity. Note: If the ground is
weak or faulty, the system may switch off at random, even if the heating
system operates correctly when checked.
• Check that the ignition flame surrounds the electrode and burns evenly
with a bluish flame. If OK replace pilot assembly. You can`t get the
• If everything is OK replace pilot assembly.
No
Heat requirement ended, system
switches off, flue baffle closes.
End of troubleshooting Repeat procedure until heating system operates properly.
• On models with vent damper check that it operates and limit switches
are present. If necessary, replace vent damper.
• Check ignition wiring, ceramic insulator of ignition electrode and ignition
gap, adjust if necessary.
• Check the ignition cable contact for signs of scorching or kinking.
• Replace automatic ignition unit.
No
Ignition spark stops as soon as
ignition flame burns.
• Check ignition wiring and ground for continuity.
• Check ignition electrode.
• Check electrical connections between ignition electrode and automatic ig-
nition.
• Check whether the ceramic insulator in the ignition electrode is broken.
• Check that the ignition flame surrounds the electrode and burns steadily
with a bluish flame.
• Adjust ignition flame.
• If this does not correct the fault, replace the automatic ignition unit.
No
Main burner ignites.
• Use MV-MV/PV terminals to check 24 V AC, closed current circuit at the
pilot assembly. If there is no voltage, replace pilot assembly.
• Check electrical connection between pilot assembly and gas valve.
If OK, replace gas valve.
• Check operation of thermostat (control).
• Disconnect 24V connection to gas valve. If gas valve closes, check ther-
mostat and connection line again.
• If the gas valve does not close, replace gas valve.
•
Check if the fuse in 24 V circuit is still working.
electrode seperatly.
6 720 804 440-52.2T