Expansion tank in un-vented system...

[macdaddy2x]

I have an unvented hot water/central heating system in my home. I recently went round and bled all the radiators, because of this the pressure in the expansion tank dropped to 0. I connected the filling line and filled it back up so it was at 1.5 bar. Is it ok to do this? What should the pressure in the expansion tank be? I guess eventually I will lose the air bubble by doing this... how do I make sure this doesn't happen/get it back?

Thanks in advance.

 

[danielp]

you should pressure it to 1.5 bar nothing will really happen atall , does it keep going to zero?

 

[macdaddy2x]

you should pressure it to 1.5 bar nothing will really happen atall , does it keep going to zero?

Since I have charged it back up it has stayed at 1.5 bar, it only went to zero when I was bleeding the rads.

Is that normal?

Thanks for the reply by the way.

 

[smoggs03]

Since I have charged it back up it has stayed at 1.5 bar, it only went to zero when I was bleeding the rads.

Is that normal?

Thanks for the reply by the way.

yeah that's normal but do keep an eye out for pressure loss it can be a leak/ or faulty discharge(check pipe outside) but a bled radiator is a leak of sorts and the pressure drops

 

[macdaddy2x]

Guys... thanks very much for taking the time to answer my questions.