We've just had a utilty room refurbished and one radiator replaced in that room where plumber drained most of the system (system was also drained with no issues in the summer for another project).
Now several rads on the grounds floor won't work including the new one and the plumber who put in the new rad says he can't see why. Rest of system heats up but I've run what must be 50 litres out of the bleed valve on one rad (keeping the boiler filled properly via the fill loop) and it's not drawing in hot water, only getting slightly luke warm.
The bleed ejects water very fast. I can believe the return may have got blocked by sludge but why can't I draw in hot water.
It's an S plan system with hot water tank and heating controlled by separate valves. Also the boiler seems to be cycling even with the hot water and heating turned off and heating a big rad close to it in the kitchen, which is keeping the kitchen nice and warm. It's always done this when just the hot water is on but now when the hot water is off...
Any ideas before I berate the plumber and have to find someone else.
I'm thinking maybe it will have to be power flushed.