central heating system problem with filling

[johnjunior]

I have just fitted a new radiator in the bathroom. To do so I partially drained the central heating system. The problem is now when I try to refill the system some of the first floor radiators do not seem to fill up. When I remove the bleed valves nothing happens - not even the sound of air escaping. Two of the five radiators feel luckwarm at the bottom the rest are stone cold. All the downstaird radiators are fine.
Can anyone tell me what to do!

 

[JPC]

what system might u have ?

 

[johnjunior]

A conventional system. Header tank in roof space

 

[JPC]

have gone into the loft and checked the ball valve is working and the header tank has some water in it (some times they stick closed due to not moving much for years)

its the small tank (cistern)

 

[jdey]

Don't forget to pee in the water tank (the larger 1) whilst you're up there, like the pros do

 

[JPC]

??
where did that come from ?

 

[johnjunior]

Checked this all seems ok Header tank full. Ballcock working as it should

 

[bones001]

have you put your heating on and tried it, have you tried getting air out of the vent in your airing cupboard? other than that it could be a blockage in your cold feed

 

[johnjunior]

Yes heating system on - bottom of rads slightly warm -still nothing when i open the bleed valves. Can't find a vent in the airing cupboard.
How can i ckeck for a blockage in the cold feed?
Many thanks for you replies

 

[croydoncorgi]

You ARE trying to bleed the system with the pump turned OFF, aren't you?? Otherwise it won't!

 

[johnjunior]

No. trying to bleed with pump on

 

[broxy]

No. trying to bleed with pump on

That will drag air in and not pump air out although you may shift the air lock.

 

[johnjunior]

Have tried with pump both on and off. Still no success.

 

[Nige F]

Don't forget to pee in the water tank (the larger 1) whilst you're up there, like the pros do

Now then, you didn`t watch closely.....The guy ****ed into a vase,tipped that into the F+E tank and then washed the vase in the big tank...me ,I`d have nicked the vase if it`d been an antique....I worked as a "Knocker" for a few years so I know a ming from a minger.( sorry jonjunior.hope you get your htg. sorted )

 

[Soggy_weetabix]

blocked air bleeds?

David