Air in central heating

[timtheenchanter]

I have a glowworm boiler with 2x 6` singles and a 4`double on the ground floor, 2x 6`, 1x 4`single and a 2`double on the first floor and 2x 4` and 1x3` doubles in the attic rooms.

The boiler is on the first floor in a cupboard in the bedroom,

I have the problem of reccuring air in the attic radiators, to the point where the 3` is nearly empty in a period of around 2 months, there seems to be no apparent leak (ie the pressure indicated by the boiler doesn't change, and is constant at around 1.1bar (as per boiler manual)

Any suggestions on what is causing this, and if it can be prevented??

Oh forgot to mention, all radiators have TRVs, if it makes a difference

 

[JohnD]

It is quite likely gas produced as a result of corrosion of the radiators.

Is there a corrosion inhibitor chemical in the water?

 

[pannierstan]

Either that or the system is incorrectly configured and either pumping over or dragging in air from the header tank.

Stan

 

[JohnD]

...header tank...

... the pressure indicated by the boiler doesn't change, and is constant at around 1.1bar (as per boiler manual)...

 

[pannierstan]

Oops sorry.

Should read more carefully.

Sorry to both of you

John is totally correct

 

[timtheenchanter]

the boiler was installed just coming up to the 2 years mark, there was SUPPOSED to be a pressure flush, and corrosion inhibitor done/put in at the same time,
Is there anyway to check, colour of water in rads etc??