Central heating connected to hot water?

[ReverendJT]

Hello,

I had a new combi boiler installed a few years ago and have just noticed that if the radiators are stone cold and I turn a hot tap on the central heating flow pipe (at the boiler) becomes almost as warm as the hot water pipe. Could this be that the two pipes are somehow linked or is there another possibility? If so what implications does this have?

Any help would be appreciated,

His holiness

 

[seco services]

what boiler etc is it ?

could be a faulty diverter valve

 

[GPlumb]

The diverter valve is malfunctioning, which boiler do you have?

/me too slow Seco

 

[ReverendJT]

Both of you are pretty damn fast!

It is a Glow worm Xtrafast 120.

 

[wedge69]

Not necessarily.

Leave the water on for a reasonably long time (i.e. while having a shower). Is it only the first foot or so of the CH piping from the boiler that gets hot, or radiators around the house?

If it is all the radiators then it probably is a divertor, otherwise someone once told me that it is just boiler over run (where the boiler gets rid of the excess heat when the hw is turned off).

I'm no expert though, but it's jsut another option before you get too worried.