Vaillant 824 Wiring Issues

[NozSpark]

What you describe is VERY bad wiring practice

Boilers and their controls should have a single point of isolation

 

[Sharpend]

Sorry to say, either I've misunderstood your post, or I'm not sure you really know what you're doing?

Are the boiler and controls on separate supplies?

 

[Andy™]

Sorry to say, either I've misunderstood your post, or I'm not sure you really know what you're doing?

Are the boiler and controls on separate supplies?

not sure, but it looks as though even if they are on the same supply, there may be a live in the boiler even if its switched off

 

[Sharpend]

Not sounding too clever?

Jim wherefore art thou?

 

[Andy™]

just goes to show, a little knowledge is dangerous. fortunately, in this case, it didnt work correctly, so obvious there was a problem and its been discovered.... before some innocent other person comes along, ensures supply to boiler is dead, then gets electrocuted because someone put a separate live supply to it...