Boiler Service, then dripping overflow.

Has he left the water inlet valve slightly open? Easily done with one of those washing machine inlet valves that are sometimes/often fitted. I replaced ours with a proper tap.

Sometimes, if it ain't broke don't fix it is very good advice. We used to get regualar service on one of the very first ever domestic video recorders, nine times out of ten any breakdowns were within two weeks after a service. Brian

If the pressure relief valve is operating, there's a good chance it'll need replacing when the problem is solved. The guys who put in a shower room for us, though very good workmen, used the PR valve on our Baxi boiler to reduce the pressure while they installed a towel rail. They should have used the (less accessible) drain valve, and needed to replace the PR valve as it wouldn't stop dribbling. The Baxi manual warns against this.

Cheers

Do you mean the tap second from the right in this photo:

It looks to me like it is fully on. You imply it should be off. i.e. turned to be 90 degrees to the pipe.

Many thanks

The valves that should be full off at usually at both end of a braided flexible hose which technically should be disconnected after filling but are usually left fitted but isolated with the taps. AFAIK it is not allowed to implement a filling loop with fixed pipework and so none of the valves in your photo should be related to this suggestion of a cure.

A weeping PRV at low pressures is an indication of a faulty/dirty valve. One weeping at 3 bar shows it is doing its job.

According the the installation manual, the order of pipes left to right is

heating flow domestic hot out gas in cold water in heating return prv condensate

so it would be useful to see a little of what goes on below that photo...

I should say that this is a direct (?) hot water system. That is to say, there is no water tank. So turning off the cold water inlet probably means no hot water.

Not relevant to your query I'm afraid, but isn't it the case that plastic fittings and pipe should be a minimum of 1m from the boiler?

A little more:

And sure enough the braided hose was left fitted.

And the boiler engineer admitted to the human error of not tightening the valves fully, after filling the radiators.

Everything is fine now.

Many thanks to all.

I was wondering the same ... at least the gas isn't plastic!

I was hoping for an extra foot, rather than an extra inch, but as it's working now, no problem I guess ...

Extra inch? It's the same photo with the same URL

Pardon me, a bit of 'puter trouble.

This is the correct URL:

Wow, a 'plumber' who can't solder!

(Actually, now it's all lead-free, it should really be a 'tinker'.)

Cheers

plasticer - surely?

Nice bit of bending on the RH pipe!

Done in Potterton's factory I suspect, judging by the rest of the install ...