Riello RDB, motor on, no ignition

airliebeach

Pump bleed valve gives good flow of fuel.
Photocell checked and cleaned reads OK.
Can't hear spark!
Disconnected motor at control unit & read 230v. Was told this should be 52v...(maybe only when motor is connected?)
Any tips?

DGOBS

Do you mean it constantly runs but no lock out?

Usually one of 2 things, either the photocell or the solenoid coil (it can be a control box sometimes)

disconnect the photocell from the control box (power off for safety!!) and run the burner like that, now if it fires after 12 seconds of run, then you have proved its a faulty PE cell. Replace

If not, if you know how, remove the solenoid, and test with a multimeter for resistance (should be aprox 100ohms) if not, Replace

Iderown

When that happened here it was the solenoid which had gone open circuit.

I homed in on that pretty fast as there was no characteristic "click" of the solenoid opening the oil flow valve.

Edited to note that the problem could have been in the control unit. After totally isolating the system from the mains, I checked the resistance of the solenoid. It was open circuit.

jimf

53 v coming back from motor to white wire

as tony dgobs says above


photocell first then control box rarely coil on riello burners there nearly bomb proof

John.G

If similar to the Riello G5X then if the solenoid is working you will hear a click, if then no ignition I think you might be able to hear the ignitor buzzing for 5 secs before lockout.
I know the photocell has been checked but if its removed then if faulty the burner should do a 12 sec purge and then lockout after a further 5 secs.

DGOBS

Jim, have replaced many on the RDB over the years (rarely on the G series though!)

Re listening for a solenoid 'click' is a good indicator, but it should be checked for resistance, as either a faulty control box, or as Jim said the rare motor issue where your not getting approx 50-53v back from the winding to the control box (on the white wire) would also prevent the solenoid from energising, leading you down the wrong hole...

I know the photocell has been checked but if its removed then if faulty the burner should do a 12 sec purge and then lockout after a further 5 secs.

note, it WILL FIRE for the 5 seconds with the PE cell removed, if that is the faulty part

Photocell checked and cleaned reads OK.

what you mean reads ok? (resistance?) to properly check a PE cell, would require a known source and LUX meter, never rely on resistance alone.

jimf

DGOBS wrote: »

Jim, have replaced many on the RDB over the years (rarely on the G series though!)

Re listening for a solenoid 'click' is a good indicator, but it should be checked for resistance, as either a faulty control box, or as Jim said the rare motor issue where your not getting approx 50-53v back from the winding to the control box (on the white wire) would also prevent the solenoid from energising, leading you down the wrong hole...

note, it WILL FIRE for the 5 seconds with the PE cell removed, if that is the faulty part


what you mean reads ok? (resistance?) to properly check a PE cell, would require a known source and LUX meter, never rely on resistance alone.

you must be getting them ould faulty coils from mr murry tony

I think 1 of each coil in 10 years tony is all I have changed

airliebeach

Cheers for all the help lads.
As it turns out, a baffle had somehow fallen down to where flame does be. Heat was backing up into motor/pump. And causing mayhem. Burner didn't lockout either, I would've thought this is would be a good lockout but anyway.
Gonna need new burner and cabinet unit thingymebob.
Think the circulating pump is OK (only silver lining I can see right now)