upstairs radiators

[Handyman7]

I have recently fired up my coal fired central heating and only the downstairs radiators are getting hot along with the hot water, the upstairs are cold but have been bled and have water in them what is the problem?

[buildersmate]

Either sludge in one of the pipes in the upstairs circuit, or extremely unbalanced circuit.
Most likely sludge.

[redbreast]

I would say sludge,drain the system making sure you open the bleed valves on the upstairs rads

[chas2008]

try shutting off all the ones that work (ie downstairs) , that often forces the air/water around the cold ones...works on my system

[landie]

I had a similar problem some time ago. It turned out that there was a non-return valve in the pipework system which had got bunged-up over the years.

[gucciman]

presuming its a gravity fed system its got to be a blocked pipe