Riello burner tripping rccb

[greenfingersjim]

Hello. Burner immediately trips the rccb when call for heat is initiated. Circulation pump and other wet side components are not causing this as work fine when boiler power is off. An earth leak in the burner but any ideas how I find out what exactly, or what is most likely to cause this. Boiler was also locking regularly recently - seemingly when hot, but now simply trips the rccb.Thanks.

 

[Terrywookfit]

Which boiler do you have??

 

[greenfingersjim]

It’s a boulter buderus Camray 5

 

[Terrywookfit]

RDB burner then, At which part of the ignition cycle does it trip?

Unplug the burner from the control panel to check if wiring or burner fault.

 

[greenfingersjim]

That’s it. The last time I tried the motor/fan was spinning for a few seconds and then it tripped.

 

[Terrywookfit]

Un plug the burner to eliminate external faults

 

[oilhead]

How many is a few seconds? If it is normal prepurge, then solenoid coil could be suspect, but at the same time, the spark is also generated, so it could be either, coil or control box.

 

[greenfingersjim]

Thanks. Just tried it and still tripped so not the burner after all. Also without the noise I could hear crackling behind panel in the picture before it tripped and smell burning. Appreciate your help.

 

[Exedon]

Standard utility model? If so nothing very exciting to burn out
Not got a built in programmer?
It's lid of time and have a look.

 

[ericmark]

I note my Worcester Bosch trips a RCD FCU but did not trip the RCBO it was previously powered from, which seems a bit strange, at moment the central heating is not RCD protected, however it seems this is OK as have a compliance certificate issued for it when the supply was changed to a non RCD protected supply by the solar panel installers.

I do wonder if there is some high frequency involved, or DC leakage, the old RCBO was a type AC, when I tried to get a type A RCD FCU I failed, fitted only one I could get, found it tripped when boiler started and removed again, some thing to look at in the summer.

It seems most oil boilers have common parts what ever the make, and maybe the spark generator or other component upsets some RCD's? It is hard to get my clamp on over just the line and neutral to see what the imbalance is, on my to do list. I don't fancy using an insulation tester on the boiler in case it causes some damage, suppose at 250 volt should be safe enough.

So what RCD are you using, has it always tripped when central heating used, my RCBO was a fusebox make, as said type AC, I am not unduly worried about not having RCD protection, but it is the only item in the house without it, the freezers and fridge/freezers from same supply have RCD sockets, cable to them is steel wire armoured, reason why no longer on the RCBO supply is the supply is battery and solar panel backed, so supplied direct from the inverter. I was rather supprised no RCD was fitted, but as said I have a compliance certificate for it less than 4 months old.

Sorry not really helping you, but just wonder if some thing to do with general oil boiler design and some types of RCD?

 

[greenfingersjim]

No, not tripped the rccb before, but has locked out a few times over last few months. Heating circuit goes through a type 1 mcb, but this doesn’t trip, only the main consumer unit rcd immediately after call for heat. Not certain but I think this means an earth leak is responsible. Earlier reply suggested unplugging the burner to eliminate this. I did this and it still tripped and I could hear crackling and smell burning behind the main control panel, so must be one of the components pictured. I’ll have a closer look later today.

 

[greenfingersjim]

It’s the manual limit thermostat. Burnt out.