Water leak in hot water system

[PhilA]

I noticed a few weeks ago getting less hot water from the kitchen and bathroom taps than usual. The problem has gotten worse until now there is no hot water from any hot water tap only cold regardless of how long the central heating is on. When I started checking pipes in the house to see if there was a leak anywhere I did not find water leaking from any pipe but could hear water running in the pipes even when all taps and the CH were off. After turning off the supply from the attic storage tank the noise of running water stopped.

The only under floor pipes in the hot water system are the supply to the boiler and the supply from the hot water cylinder to the kitchen sink. The radiators are still toasty warm but no hot water from either the kitchen or bathroom taps.

I suspect the problem is in the supply to the tap as the radiators are ok, but before I start digging up floors can anyone suggest where I should start looking? The supply to the boiler to the kitchen tap?

 

[ChrisR]

"After turning off the supply from the attic storage tank the noise of running water stopped. "

Do you mean the loft tank is continually filling?

The noise could be air in the pipe which the boiler uses to heat the hot water. There may be a bleed point to let it out, near the cylinder.

I have to say I'm guessing , because you haven't described your system at all.

 

[PhilA]

Yes the loft tank is continually filling.

Sorry for not describing the system better but it is shall we say complicated. I have a feeling it was Butch and Sundance Contractors that installed the system before I bought the house.

Mains supply enters house and splits one feed going to the kitchen sink one feed to the loft storage tank. Hot and cold feeds out of the lost tank come downstairs. Cold water feed goes to the bathroom taps. Hot water feed goes to the hot water cylinder and under the floor to the central heating boiler. The feed out of the hot water cylinder splits one branch supplies the bathroom taps and the other branch goes under the floor to the kitchen tap.