Cold rads upstairs - Bit odd...

[neds]

All the rads in the house were working fine couple of weeks ago, anyway all the upstairs rads dont get warm. The incoming pipes and bottom of the rads get warm OK. Tried the usual bleed but nothing came out of the rads! Seems like the rads are half empty which is very strange.

All the downstairs rads are fine, checked the pressure gauge and its reading 0 however cold water and downstairs rads work perfect. Possibly duff gauge? Filled up using the filling loop but the gauge never went up so not sure what the real pressure actually is!
Turned downstairs rads off to force the water up but still nothing...

Any ideas what might be going on here?

Cheers

 

[Timmyturtle]

Bleed the rads with boiler off

Tap the gauge whilst filling as they can stick sometimes

Should be around 1 bar

Does the upstairs have trvs that are stuck?

Obviously if you bleed then you need to top up the pressure

 

[neds]

Cheers. Yeah bled the radiators with the boiler off. Unstuck the TRV's although they seems fine when pumping them. Did tap the gauge at the time but still wouldn't move.
Problem being no water came out the rads when bleeding, Only air hissed out...

 

[Timmyturtle]

In that case there is air in the system which needs to be bled out.

The gauge is less sensitive when there is air in the system as air compresses easier than water

Bleed out the air from the rads

 

[neds]

How would you bleed the air from the rads? When I bled the first time air hissed out then that was it nothing else? It just seems like all the upstairs rads are like half full if you get what I'm trying to say...

 

[Timmyturtle]

Just have to keep bleeding and topping up the pressure when it stops coming out
Eventually water will come out

 

[neds]

OK cheers, bit worrying why all the rads upstairs had drained to that level, pretty sure there aint no leaks...