Play the motorised valve few times then set it back AUTO. To check it allow hot water from the boiler pass through, feel the piles on either sides. If no hot water passes through then the valve is faulty.
In emergency you can override the valve by manually locking it in the 'MAN OPEN' position
Select central heating only on the Timer or Programmer and then the Boiler should fire at maximum and off at minimum setting of the Room thermostat. If this does not happen then the room thermostat is faulty.
When the pump runs, its vibrations can be felt. Noise can be listened with the help of long insulated screwdriver.
You may access the pump shaft, after removing the pump vent screw at the back of the pump body. Expect water spillage and take care.
The pump shaft should spin freely, try and accomplish this using a small narrow screwdriver, if this is not possible the pump is faulty.
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