Help - cold rad is doing my head in!

[richarddavies]

I live in a semi-house which has just had all new rads put in. All rads (upstairs and down) are very hot to the touch, apart from one which has some heat, but is virtualy cold.

My boiler is a Potterton Suprima less than 1 year old and is located in the kitchen. The cold rad is located in the hallway (which is quite large and bloody cold). The inflow/ outlow valves are now fully opened on it, and I've tried fiddling about with them to different settings, but the rad is still cold.

I've also bled the rad and all air has been taken out.

The odd thing is the inflow pipe is very hot, and when I syphon the inflow the water comming out is hot. The outflow pipe is cold.

It seems to me, the hot water is not being pulled through the rad from the inflow pipe, as if there's a blockage? But the fittings and rad are all new!

Any ideas? please can you help? Many thanks
Richard

 

[gigz]

Has the rad ever got hot If not maybe the return pipe is kinked or too much solder has been used on the manifold (thats if minibore pipe has been used) if its 15mm there could have been two plugs in the rad but the plumber should have made sure all rads were warm before he left the job. Close the TRV's on all other rads in case its an airlock and that should push it out. If this does'nt solve it call your plumber back out.

 

[MANDATE]

My thoughts on your problem. If you have a thermostatic radiator valve it may be stuck in the closed position, so when you think you've opened it you may not have done so. If this was the case it would affect the bledding of the radiator. If both valves are fully open then the restriction maywell be an 'air lock' in the pipe work and bleeding the radiator is not going to move it. gigz however has covered this.