Can someone offer some advice please?
The last rad on the system (no TRV) has been cold for a fewweeks now. The flow valve is hot but theradiator does not heat up. The returnvalve is cold (obviously) as not hot water is going through the radiator. I have checked the lockshields and they seemok. I’ve taken off the radiator andflushed with a garden hose (small amount of black water before being a lightbrown colour).
While the rad was off, I opened each lockshield in case ofan air lock in the pipe. The returnvalve was strong immediately. However. Theflow valve was much slower with black water for a few seconds before beinglight brown. The strength of the flowfrom the flow valve is very poor (noticeably different from the return valve). Does this explain why the radiator is notheating up?
Does it mean a faulty flow valve, blocked pipe or somethingelse?
I’d appreciate any help.
Thanks
drewb