Hiya, Been living in my current property for 18 months now and for the past year or so, I had closed the hot water valves on a number of radiators towards the front of the house. As it's getting cold now, I went to open them and found that the radiators remained cold even when the heating is on. I felt the pipes under the radiators and they are not warm. I guess this means there must be a block/several blocks in the pipes? Other radiators in the house which I used frequently get hot. What's the best way to deal with this situation? Thanks in advance.