Riello DB 16 SM C01 TC A0 FS1 T250 Installation, Use And Maintenance Instructions page 38

6.4 Problems and remedies
If the burner does not work properly, first you must:
1 check that the electric connections have been correctly performed;
2 ensure that the fuel is delivered correctly;
3 check that all the adjustment parameters (e.g. boiler water temperature or boiler steam pressure) are correctly set.
Fault
The burner does not start
The burner does not start and a
function lock out occurs
The burner ignites but then blocks
The burner starts and then locks out
After pre-purge and safety time,
the burner goes to lock-out and the
flame does not appear
The burner goes to lock-out right
after flame appearance
The burner repeats the starting
cycle without lock-out
During operation, the burner stops
in lock-out
Lock-out when burner stops
Ignition with pulsation
18
CHAPTER
Possible cause
• No electrical power supply . . . . . . . . . . . . . . . . . . . . Close all switches - Check connections
• A limiter or safety control device is open. . . . . . . . . Adjust or replace
• Flame control lock-out . . . . . . . . . . . . . . . . . . . . . . . Reset control box
• Control box fuses blown. . . . . . . . . . . . . . . . . . . . . . Replace
• Erroneous electrical connections. . . . . . . . . . . . . . . Check connections
• Defective flame control. . . . . . . . . . . . . . . . . . . . . . . Replace
• No gas supply . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Open the manual valves between meter
• Mains gas pressure insufficient . . . . . . . . . . . . . . . . Contact your GAS COMPANY
• Minimum gas pressure switch fails to close . . . . . . Adjust or replace
• Air pressure switch in operating position . . . . . . . . Adjust or replace
• Flame simulation. . . . . . . . . . . . . . . . . . . . . . . . . . . . Replace control box
Air pressure switch inoperative due to insufficient air pressure:
• Air pressure switch adjusted badly . . . . . . . . . . . . . Adjust or replace
• Pressure switch pressure point pipe blocked . . . . . Clean
• Head wrong adjusted . . . . . . . . . . . . . . . . . . . . . . . . Adjust
• Fault in flame detection circuit . . . . . . . . . . . . . . . . . Replace flame control
• The solenoid VR allows little gas through . . . . . . . . Increase
• Solenoid valves VR or VS fail to open. . . . . . . . . . . Renew the coil or rectifier panel
• Gas pressure too low . . . . . . . . . . . . . . . . . . . . . . . . Increase on the regulator
• Pilot burner does not operate. . . . . . . . . . . . . . . . . . Check
• Defective ignition transformer . . . . . . . . . . . . . . . . . Replace
• Erroneous valve or transformer electrical . . . . . . . . Repeat connections
connections
• Defective control box . . . . . . . . . . . . . . . . . . . . . . . . Replace
• A cock down-line of the gas train is closed . . . . . . . Open
• Air in pipework. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Bleed air
• The solenoid VR allows little gas through . . . . . . . . .Increase
• Max. gas pressure switch operates. . . . . . . . . . . . . .Adjust or replace
• Defective control box . . . . . . . . . . . . . . . . . . . . . . . . .Replace
• Mains gas pressure is near the value to which. . . . Reduce operating pressure the min. gas
pressure switch gas is adjusted..
The repeated drop in pressure which follows
valve opening causes temporary opening of the
pressure switch itself, the valve immediately
closes and theburner comes to a halt. Pressure
increases again, the pressure switch closes again
and the firing cycle is repeated.The sequence
repeats endlessly. And so on.
• Fault on air pressure switch . . . . . . . . . . . . . . . . . . . .Replace
• Max. gas pressure switch operates. . . . . . . . . . . . . .Adjust or replace
• Flame remains in combustion head or flame . . . . . .Eliminate persistence of flame
simulation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .or replace control box
• Poorly adjusted head . . . . . . . . . . . . . . . . . . . . . . . . .Adjust
• Poorly adjusted air damper, too much air . . . . . . . . .Adjust
• Output during ignition phase is too high . . . . . . . . . .Reduce
6
Maintenance
Recommended remedy
and train
of minimum gas pressure switch.
Replace the gas filter cartridge