Radiator cold at top even after bleeding

[keiron99]

Our heated "towel rail" isn't heating at the top. It's brand new, connected to a brand new big bugger WB boiler and not too far from it either. However, when I bled it, it let quite a bit of air out but no water started to flow. Consequently, more of the upper rails are heating up, but the top 3 stubbornly refuse to do so. There's no more air to let out, and it just seem that the water isn't reaching the top rails.

Does anyone have any ideas how to fix this myself? I'd rather go cold than get the miserable filthy sod of a plumber who installed it in the first place out again!

[Ian Stirling]

It's not impossible that it may have gotten clogged somehow.

I'd take it off, and wash it through with the hosepipe.

[Jim Alexander]

check your pressure gauge

Jim A

[OG]

Is it a room height one? It may be relevant

[keiron99]

The top of it is about 4 feet off the ground.

[OG]

OK probably not relevant then.

[Harry Bloomfield]

[e-mail] presented the following explanation :

If it's a combi check the pressure gauge, otherwise make sure the header tank has water in it and is well above the top of the towel rail. For both make sure you are bleeding it with the pump off - as a pump could be creating a slight vacuum at the towel rail.

[Ed Sirett]

Is this a sealed system (please read the faq below)?

[Andy]

You haven't enough water in your CH system to fill up the radiator beyond the level it has stopped at. That is why people are telling you to check your pressure gauge, as that needs to read high enough to force water up to your upstairs radiators. If you have a sealed system you need to admit more water into it then bleed the radiators again until they fill.

Andy.

[Dave Plowman (News)]

Is the top of it higher than the top of any other rad in the house?

[visionset]

Is the radiator level? If the bleed end is lower than the other air can accumulate in the other end. I'm not sure if CH additives stop the water dissolving oxygen or allow it as normal but render the oxygenated mix somehow less corrosive. If the former then eventually the air will redissolve in preference to the air you can get out of the system elsewhere. Actually I'd like to know which it is... ?