1930s property some lead piping but mostly a mix of copper and plastic. Boiler is roughly 4 years old with one of those magnaflow things. On the times I have switched the water off, and then back on again significant amounts of crap comes out of the hot tap the closest bathroom to the boiler. discoloured brown with coppery brown rust like bits. In the morning the sink hot tap runs off coloured for the first draw.

There is evidence of some water damage around the boiler but it looks old. could the old boiler have failed and dumped loads of crap in the system? How do I sort this out? boiler service? Or get a plumber round?

Probate so can’t ask previous owner

ok need a bit more info.. combi boiler? turned the water off then on again .. via the stop tap?

dirty water can come from anywhere.. combis are clean if not they fail very quickly.. your magnaflow only protects the central heating system not the hot water from the taps..

any discolouring of the cold water?

Combi I believe no tank that I can see. It is a valiant Eco plus. Water was turned off via the stopcock and may have been for sometime as there were no isolator valves when the washing machine had been removed, property has been empty for several months.

I’d switched the water on / off several times whilst trying to fix a badly leaking tap. I don’t believe there is any discolouration from the cold. When I took the filter off the kitchen mixer it also had rust like silt blocking it up. I have the water board round on Monday to test for lead in the water

Little bump for the morning crowd. Anyone?

Sounds like you may have some galvanised pipework somewhere that is corroding.

Or it could be sediment that has settled through lack of use in the plate heat exchanger.

If the combi had failed the pressure gauge would probably show something.

Or it could be the water company has been carrying out work in the area and debris has entered the main. I would suggest a good long flush, 30 mins or so. Also turn the tap off and on trying to agitate any sediment that has settled.