Can I Fit New TRV Without Draining Down (Worcs. 24i Junior)?

[TheOP]

Are there any air vents on my Worcester 24i junior that I can close, to allow me to fit a new TRV without draining down?

On my brother's Broag combi, we can close the air vent on the pump and the AAV on the top of the boiler, and change a valve without draining.

Is this possible with the Worcester, if yes, where are the valves that need closing?

 

[Andygasman2010]

Where is the TRV in relation to the boiler? I never close any vent when changing rad valves on sealed systems. Just drop the pressure and away you go! Just be quick and have a small dish/towels on hand.

 

[petit_pablo]

Theres a AAV on the pump housing in the junior.

I find that for some reason these need closing off on the worcesters.

 

[JPC]

or isolate the boiler from central heating!