Electrics cut out when central heating switches in.

[Ian1943]

Each year at the start of the heating season the hot water to the radiators fails to circulate. So each year I have to dismantle the cover to the pump and free it as it has blocked with silt. This year, now, intermittently the boiler fires up and the trip switch trips and the whole house electrics cut out.
The Corgi engineer called and the system worked OK - He was unsure whether the pump was at fault or the controller was faulty. One hour after he left, half way through typing this question, the electrics cut out again!
Does any one know which part of the system is likely to be at fault.
The pump is a Grunfoss and the controller is Lifestyle LP522. Thanks for any advice offered.

Ian

 

[MANDATE]

seems like pump is the most likely culprit

//www.diynot.com/forums/viewtopic.php?p=1485069#1485069

 

[ChrisOxford]

Agreed

Yes, almost certainly tripping your RCD, which means you have an imbalance in the current flowing in your Live and Neutral wires, usually because there's an electrical leak between live and earth somewhere.

In a CH system, the commonest cause is water leaking into an electrical component - the pump is the most likely culprit by far here.

An electrician with a Megger could confirm, but replacement is probably wise, unless it's just temporarily soggy because of your disassembly.

(Reminds me of a friend's CH which did the same thing when it was switched on - just before Christmas. That was the big clue: she'd pinned her cards to ribbons which were in turn pinned to the picture rail. A quick look revealed that's where the installer had run the cable to the room stat One pin had caused a lovely N-E short. )