Thanks for all the feedback, some usefull points to try. On the general arrangement of plastic pipes I'd have to agree that its all a bit of a mess. Wish i'd taken that up with the plumber at the time. Unfortunately there are no isolation valves on the connections apart from the connection...
Now also wondering if the surrey flange is the wrong flange. Should I have fitted a Warix flange instead. Whats the difference between the surrey and the warix ? I've read somewhere the surrey can restrict the flow ? Want to avoid drilling a hole in the side of the cylinder for an essex flange...
I've recently installed a new bathroom on the same floor level as a gravity fed hot and cold water system. I've installed a twin negative head pump as per the photo but still have problem with the hot water running through the pump. Cold water through the pump is fine. I've got a surrey flange...