when central heating or hot water is put on it lights as per normal,after 2 or 3 minutes it starts banging and clicking and pilot light goes out,therefore no hot water or warm house! i have a Grundfos Selectric Super pump which doesn't sound any different so im sure its ok...Please help with things i should check

Michael Hillier, January 2008

ball-valve is working ok. Is there a flush solution i can buy to remove any "muck" that may be preventing proper flow? Is there a simple way of testing the pump?

Michael Hillier, January 2008

hi,,
if you can hear the pump running the fault possible lies in the loft. go to the smaller tank and see if the ball valve is floating in the water,quite often the ball valve will stick causing the system to run short of water...
hope it helps.

terry ellis, January 2008