I think I must have an air lock in my central heating system, it
consists of a wall mounted boiler, cold water tank and header tank in
the loft, the water pump is in the airing cupboard next to the hot
water tank, the pump straed making a noise and the radiators were only
getting warm at the bottom, I tried to bleed them without any luck so
i removed the pump which is only 2 years old, it was completley dry
inside. Any idea's how to remove the air lock?