Hi,

I would be grateful if people could help me with this. I just happened
to go up into my loft this morning whilst the central heater and the
hot water were both on. The shower was running so I guess the boiler
was heating the heating loop.

Anyhow when I got into the loft I could see that there was very hot
water going into the header tank from the overflow pipe (that comes
from beloe and the airing cupboard). The water in the header tank was
very very hot ?

Why is this happening, and how do I stop it ? I don't think that the
steam it was generating is much good for inside the loft space.

Many Thanks

Chris

"Wildey" wrote in message
om...
Hi,

I would be grateful if people could help me with this. I just happened
to go up into my loft this morning whilst the central heater and the
hot water were both on. The shower was running so I guess the boiler
was heating the heating loop.

Anyhow when I got into the loft I could see that there was very hot
water going into the header tank from the overflow pipe (that comes
from beloe and the airing cupboard). The water in the header tank was
very very hot ?

Why is this happening, and how do I stop it ? I don't think that the
steam it was generating is much good for inside the loft space.

Many Thanks

Chris

It's called "pumping over" and usually results from the fill and expansion
pipes being incorrectly connected into the system. It is a BAD thing, and
needs to be stopped because it wastes engergy and draws air into the
system - with air-lock and corrosive consequences. You can sometimes prevent
it by turning the pump speed to a lower setting - but this may result in
insufficient flow to heat the house properly.

Try that first, and if it doesn't work, draw a diagram of your system,
showing exactly where the feed and expansion pipes are connected in relation
to the boiler, pump, hot water cylinder, and each other. Put that on the Web
somewhere, and post a link to it here, and someone will analyse the problem
in more detail for you.

Roger