Boiler / hot water problems Drainage and wastage systems and plumbing help, advice and answers

[Blacktom]

Recently moved house, the boiler was meant to have been serviced. Invoice provided, but suspect that this was done by a friend of a friend! Unfortunately the people who sold Us the house no longer live in this country. The problem (s) open a hot tap anywhere in the house and cold water only comes out and no hot water except for one bath tap. Open this tap and it then allows hot water to come out of other taps but you must leave it open while you use another tap! The boiler is a combi boiler, relatively new, believed to be c. 2008 ish. The boiler is in an upstairs room next to the bathroom with the hot tap that when open allows water out!! It was suggested that we would need to open up and view all the pipes hot and cold through out the house, considering most of these are hidden in walls, ducts, behind tiles etc etc I do not want and assume I don't need to. Anyone got any ideas please!!!!

[plumbbob]

When the system is cold, open one of the "cold" hot taps half way. Go to the boiler, count to 20 and check if any of the smaller 15mm pips are getting warm. If not, go to the bath and open the hot tap there. Return to the boiler and check the pipes again. Explain here what happens.

[zeeman]

I have had a Vaillant EcoTEC Exclusive 838 Condensing Combi Boiler, installed in Aug/2013
at first things looked fine then I noticed the pressure bar started going down, I would have to refill every 24 hours. On many occasions I bleed the radiators, I called my plumber back he could not understand it so he even crawled under the floor boards to see if there any leaking pipes and he said every things fine there.
I eventually bought Fernox F4 Superconcentrate Leak Sealer, which seemed to do the trick hence the pressure bar is stable now. the problem I am getting now is that my boiler sounds like every now and then (twice in the day once at night) its resetting it self, note I don`t mean its firing up .
is this normal ?

[plumbbob]

The activity noises are most probably normal. The Ecotec boilers constantly keep a small amount of hot water available in the primary circuit to reduce response time when hot water is called for.

The boiler also exercises itself periodically to help reduce the possibility of seized mechanical parts.