Can dust cause an RCD trip?

oldskoo1

Most bizarrely our electricity cut off this morning.

Never happens and as I reset it, tripped again. Every time I tried to reset the boiler would come on and then trip.

Long story short, the CH programmer was not meant to even be demanding hot water or heating so that was odd. I turned off the boiler but left the programmer on. It continued to turn on the pump for CH despite being programmed to be off until 3:30pm.

Anyway. Convinced it was that, I turned it off and took it off the wall.

Lots of dust, hovered it and the connection plate and since then no more cutting out.

Could dust cause the cut / trip?

It is old, sticker said 2004 on the back.

Heedtheadvice

Dust can cause a trip. Anything that reduces the insulation between the phase and earth or neutral and earth (or in fact any path that puts the phase and neutral currents out of balance for long enough) that is sufficiently low can cause a trip.


Dust problems are less common as depending upon dust type they may or may not be insulating. Far more common is dampness or equipment failure.

bris

Its not the dust, you have an earth fault some where, get some one in to find it.


If it's only tripping when you turn the boiler on you obviously have a fault with the boiler.

oldskoo1

Miraculously since removing the programmer and vacuuming the plate and programmer which was covered in quite a bit of black/grey dust and some plaster the tripping has completely stopped and the programmer has been behaving normally.

I’ll see how it goes and hopefully it will have fixed it. Otherwise I’ll jist fit a new one.

coffeehound

The dust might have built up behind sprung contacts (perhaps due to the rotation of the clock) causing a set to stay connected after they should have separated, thereby causing a short circuit to be created somewhere

coffeehound

The black dust indicates dust causing mischief between the contacts, so it might be worth giving the contacts a clean to stop them eroding any further using something like

https://www.ebay.co.uk/itm/Electrolube-CCS020-Contact-Cleaning-Strips-Pack-Of-20/121580249375