Found the cause, I thought I had opened all the taps "to let out trapped air"
but had missed one hot tap. Opened it and let it expel air/water now all is fine.
Two arms and two legs I think :(
£3200 for just boiler, flue and magnetic filter installation, including two years free...
Hi folks, thanks for the replies.
The RH light (green) comes on briefly and the code I get is s17 = pump overrun.
I understand the green light is for "warm start" which I have turned off.
I have not asked the fitter, can't find his phone number at moment.
It was a British Gas installation...
I have just upgraded from a Vaillant Turbomax to an Ecotec Pro 28 condensing boiler.
I am wondering why the boiler becomes active for a short time when I run a cold tap.
It does not fire up but a pump or something runs for about 10-15secs when the cold tap is shut off.
Is this normal...