hello my heating is working but my rads are not getting very hot they dont need bleeding becouse they are warm on the tops but its like thay are on
low
The system sounds like it might be suffering from corrosion (sludge). I assume it is fairly old?
Probably best to introduce a cleansing chemical such as Fernox Superfloc or Sentinel X400, operate system for a few days, then drain down and re-fill. Add 1 litre Fernox MB1 or Sentinel X100 Corrosion-Inhibitor when re-filling system.
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