Potterton profile 80L trips RCD at consumer unit

Hi. Serious problems... Two days ago I found my RCD trippe din the CU of my power supply. Trial & error reveals that whenever my boiler comes on the RCD trips in the mains and we lose all the power on the RCD...

Looking at the boiler, some bright spark has installed the pump directly above the boiler and the connection to the pump has been leaking onto the boiler and running down the side. Eventually into the circuts at the bottom...

So I put a funnel uner it till I can get the isolating value off & replace it. Meanwhile trying to dry out the unit to get it to work...

After two days of drying it out, the damn thing still trips the RCD. Even when I set the thermostat on the front to 0. Meanwhile I have no heating or hot water...

I tried a hair dryer, but no luck so far... Is it dead? Where should I look for a short? I can't belive after 2 days there's still enough moisture in there to trip the RCD... (i.e. where's the best place to direct the dryer to try & get it to light. presumably when it's running it'll dry out 100% in no time at all... If it is the moisture doing it & not a busted boiler).

(Or could it be the pump busted?)

Meanwhile getting a plumber out seems impossible... Grr! Why don't they ever want to come out? You wait hours for them to not turn up when they've promised... And no explanation why...

TIA
Hamish.

Did the pcb get wet?
Is there a stain on it?

No stain that I can see. The unit is still getting power (ouch, almost got me before I realised it was powered all the time & not just when running , it's when it starts that something is leaking to earth. It doesn't seem to be the gas valve... I can pull the connection and everything still trips.

Now I assume that the board gets power full time, to run things like the frost protection etc. Which means perhaps it could be the pump? (And the water leak is either a false lead or a consequence of the pump failing, although it'd take a spectacular failure to vibrate the value lose enough to drip I would have thought). Anyone ever seen a pump go out like that?

H.

you could remove the supply from the pump and see if that stops the tripping (turn the boiler thermostat down as it will get hot very quickly if you let it fire)

Primary water contains various chemicals and deposits (including magnetite) that may leave a conductive film on whatever they dripped onto, even when the water has evaporated.

Pure clean water is not very conductive, it's the impurities that cause the trouble. If you trace the prob to a particular part, and are about to replace it, you can try rinsing it in deionised water first and letting it dry. This sometimes works (especially on things that have had tea or coffee spilt on them)