Thorn M boiler is it possible to reset

[paulmol]

When connecting a honeywell 4043 motorised valve the boiler rcd shut off the electrical supply. This seemed to be related to connecting the brown wire from the valve which connects to the room thermostat.
Potentially offending wire is isolated but rcd still trips. Is there any way of resetting the boiler.

 

[EFLImpudence]

Not sure why you are asking about resetting the boiler.

If the RCD trips after you have installed some wiring (when it was alright before) then you have done it incorrectly.

Does "When connecting the brown wire" mean you are working live?

 

[Terrywookfit]

There is nothing to reset.
These boilers had only a thermostat and solenoid. (plus a programmer if fitted) I doubt it would still be working though.

Check your wiring , Brown opens valve, blue = neutral yellow and green = earth. The other two wires are a switch.
Sounds like you have an earth fault due to wiring wrongly.
Try disconnecting the g/y wire to m/v TEMPORARY

 

[paulmol]

I was not working live and the connection is not obviously wrong. The wire is now isolated, that is, taped up and should work as the connection of that wire was the only factor that was linked with the rcd cutting the supply. The hope is that when the boiler cuts out and the fault is cleared it can/ needs to be reset. That would certainly be the case with more modern boilers.
A potential factor is that the valve was kept open and the re-introduction of working again by connecting the temperature wire caused an overload. Either way keeping the valve open and isolating the temperature wire would be restoration of the pre- rcd trip situation.

Any help would be appreciated as I just need some heat and although I am changing the boiler that is at the tail end of other enabling works such as building a loft conversion.

 

[EFLImpudence]

Is the CPC/earth wire perhaps being wrongly used as the switched live and the wires are not what you think they are?

RCDs detect earth leakage, not overload.

 

[jackthom]

If the rcd is still tripping make sure you haven't somehow connected Neutral and Earth together, or almost any of the wires and Earth, in the valve wiring.

I'd be inclined to remove the valve wires completely and start again.

 

[paulmol]

Starting afresh and organising the wiring was beyond me but fortunately not my son-in-law. This was however necessary and identified a blue wire from the room thermostat as not being connected and the earth as being the neutral. Not surprising that the mcb was triggered(not the rcd).

Thank you for all the useful comments which were helpful in avoiding blind alleys and following the more productive course