One radiator works, 12 do not...

[YarnMit]

Grateful for your thoughts on this. We have just moved into a house, its only 8 years old. Having trouble with the majority of radiators in the building, they are stone cold. One radiator is fine. More detail:

The house has an ICOS He15 boiler on the ground floor. This appears to be firing properly (correct light displayed, steam coming out of flue). The top floor has a Megaflo Heatrae Sadia immersion heater and a Siemens programmer, with the correct times programmed in and a manual option. The immersion heater is very hot when 'on'. The hot water from the taps is fine, but the radiators in the house with TRVs are completely cold, with one exception.

The living room has a Siemens Thermostat, and this is working well - the radiator in this room (without TRV) warms up when CH is on, as per the programmer.

The hallway has the same thermostat and radiator, but this one is completely cold.

Are there any suggestions, have we missed a simple trick, or does this sound like a more serious issue?

Thanks.

 

[PrenticeBoyofDerry]

It could be that the TRVs have seized or jammed and the pin needs freeing.
http://www.youtube.com/watch?v=wqku_Rc_YuI
Could also be air in the rads and need bleeding, also check that the lockshield valves are not closed.

 

[ianmcd]

why do you have the immersion heater on ? it will be a lot cheaper to heat the water with your gas boiler rather than use the immerser that is only there for an emergency back up