i am an heating engineer--from what you have said sounds like you have
a blocked cold feed-very common this time of year--i have had 4 this
week
which means you have not enough water in system
if you take your big screw out of the pump and see no water dripping
then it proberly going to be your cold feed blocked--(if the pump is in
the airing cupboard)
also when the screw is out you be able to see or feel the pump running
just gentily poke a screwdriver in there --if theres no noise then its
your pump

a good tip ,,put your heating on occasionally in the summer --just for
minutes becuase it doesnt half help--so many people leave it off for
6months then expect that it going to work--if you didnt start your car
for 6months would u expect it to start?


Hi thanks for the reply. How would i go abouit unblock in the cold
feed? I have opened the big screw (very nerve racking didn't know if I
was going to get showered with water!) and no water came out. I can
turn the motor and have turned the hot water on whilst the screw was
removed and can see the motor turning.