Calling PigletJohn, fountain of knowledge

[lashy]

Hoping you can point me in the right direction? 2x overflow pipes clearly coming from the eaves - some kind of water tank in the loft. Suddenly (first time I’ve ever noticed in 8yrs) - one pipe is lashing out water. Had a new condensing system boiler fitted by British Gas 3 months ago (replaced a non-condensing system boiler) is the only change we’ve made. Any thoughts on what might cause an overflow up there? Not sure whether to call a plumber or British Gas / central heating check (CH working perfectly fine).
TIA

Could be a ballcock issue with one of the tanks in the loft that's making it overflow

I’ll check that out. Much appreciated, thank you.

Fair point and I agree - I'm a very handy woman myself; however, over the years I've seen many threads where PigletJohn has come up trumps and seems incredibly knowledgable with all things house maintenance, hence my question hoping to catch his attention. The thread is not exclusive to him and any contribution is gratefully recieved.

DIY in general, no problem / I'll give most things a go.
Plumbing is something I'm not great with and don't want to exacerbate a problem

Yes, ball cock issue most likely. Plumber first as unlikely to warrant a gas engineer. Haven’t seen Pigletjohn around in a while, though I may just not have been noticing so much…. So sick of my own property dramas I haven’t been on the page so often!!😆

Thank you all. Chased the overflow pipe back to one (of two) water tanks. Transpires the ball cock was completely submerged, as the valve it serves has failed, hence the tank constantly filling and subsequently overflowing. We now know the root of the problem and can get it repaired.

You can turn off your main stopcock which is probably under the sink while you I investigate.

Start by going into the loft and seeing what you have. You probably have a large and a small water tank. Take a piece of string up with you. Post photos of what you find.

Inside each tank will be a ball cock like in a WC cistern. The string is to tie the ball float to some convenient piece of wood to lift it above water level, which should close it and cut off the water supply.

If it doesn't, the fault is elsewhere, for example a mixer tap, especially if you have a ceramic mixer with a single joystick controlling the hot and cold mix.

Thank you PigletJohn. My Husband has already shut off the relevant isolation valve whilst he explored further. Raising the ball cock arm slowed the flow down but excess pressure would be needed to make the valve actually work and stop the flow completely - he didn’t want to risk snapping it, hence turned the water off. He is getting the whole arm and ball cock replaced today.
Sod’s law that it suddenly broke as the house is [supposed to be] going on the market on Tues 😣but we clearly need to resolve this issue first.
thank you for your help. I’m at work today so won’t be able to come back to this thread until this evening at least.