central heating

[neil1975]

all the radiators in my house are hot bar one, which in cold. why is this?

[drdrmrgn]

It has air in it! You need to bleed it with a special key.

[theshedman]

Hi neil, is the radiator cold completely or is there a bit of warmth at the bottom of it. If it is the latter then bleed it as drdrmrgn says. If not then it is possible that it has been turned off at the lockshield at some time. That is the valve at the opposite end to the on-off valve which is usually the smaller of the 2.

[gucciman]

if its a downstairs rad then its probably not going to be air as air rises to the upstairs rads.

if the shedmans suggestion isn't the answer then id be suspecting a faulty thermostatic radiator valve (if u have one)
take the head off the trv and see if the rad then gets hot.

is the pipework directly below the valves hot?