Combi cebntral heating problem

[reneel]

my brother in law's combi boiler has a central heating problem, whereas the hot water works ok but the central heating won't fire up the boiler

the pressure relief pipe was also dripping she said (he called it overflow pipe)

any ideas? expansion vessel charge/problem?

 

[Burnerman]

Check that there's about 1 bar of pressure in the system, and try again?
John

 

[reneel]

The gauge reads 0 !!

 

[Burnerman]

Repressurise the system up to 1 bar by introducing cold water into the boiler via the filling loop - often a braided flexible steel pipe with a tap on each end - and try again!
John

 

[reneel]

i did that but what happens is this the gauge rises and the pressure valve releases water

 

[Burnerman]

Alas, thats often the case with pressure release valves....once open, they don't like to shut off again.
You could try operating the thing manually to see if it resets, if you feel confident with doing that. Often its just a turn valve knob on the thing, which is spring loaded. These things automatically open at 3 bar.
John

 

[reneel]

thanks, I'll try it, should it stop after?

 

[Burnerman]

If you're luck is in, then yes - the valve should close and seal again. In reality, they have a mind of their own but its sure worth a try!
John