Firebird oil boiler non starter

[wolbut]

Hi - i have a Firebird combi 90 oil boiler - working fine until last week when the flow switch split - turned off the mains supply to it and isolated the water - fitted a new switch 5 days later -turned water and power back on & tried to restart it - the blower/fan is running but the burner does not fire - it does not even try to fire - any ideas ?

 

[kimbo]

Has it got a rdb burner that is the one with the red plastic cover surround. If it has it is a classic symptom of a faulty photocell. To check turn off boiler, open top of control box and remove brown and blue wire of photocell (just pulls off) start boiler again, if it fires and then goes to lockout then that confirms a faulty photocell.

 

[wolbut]

thanks Kimbo - its a Riello burner - i will try pulling the wires to the cell in the morning ( its an outside boiler and its dark)

 

[wolbut]

Thanks Kimbo but the photocell is soldered in place on a PCB so could not disconnect it and do the test

 

[kimbo]

It just slides off frontwards

 

[wolbut]

Top man - yes it slides off -- unfortunately it still would not attempt to start - thanks anyway

 

[kimbo]

In that case its probably the control box

 

[wolbut]

Hi Kimbo - yes - i think you are right - thanks for you help

 

[wolbut]

Hi Kimbo - fitted a new control box and photocell - still no joy !

 

[kimbo]

Go through the sequence of what exactly happens.

 

[Jimmeh]

Oil supply not bled through??

 

[wolbut]

Hi Kimbo - not a lot happens ! -- when i switch the elecs back on the blower runs and thats it ! doesnt try to fire - i made sure the stat is calling for heating - but as its been off it should start anyway to build heat for the hot water circuit - and i have made sure its getting a supply of oil - at least its getting to the pump - maybe its the coil on the solenoid ?

 

[kimbo]

The burner under normal conditions would go to lockout if it did not fire, the control box controls the sequence of what everything does.
Follow this link and go through the procedure systematically.
Riello Burners UK - FAQs > General

 

[Jimmeh]

my mistake did not read the original post correctly!
If the Ignition Probes had somehow been knocked out of alignment, (not that I see how they could have been), It would still lock out though wouldnt it :-/

 

[wolbut]

Thanks guys - followed the link - only have continuity on the blue-black wires so i will try a new coil -- getting 55v on the white wire; 2volts out of limits but it may be my meter (not been calibrated for a looong time)
will let you know the results

 

[wolbut]

Hi Guys - fitted a new coil but no better - checked continuity of the new one against the old one - both only have continuity on one pair of wires - i reasoned that the new coil being new in OEM wrapper was most likely to be ok - started again from scratch : cleaned the nozzle on the injector(it was clean) very slight adjustment on the electrodes - refitted the new control box and she started to fire up - after a couple of lockouts all is well - refitted the old box and it did not work !
So with your help i have fixed it - must have been a combination of faulty control box and electrodes out of spec - thanks again