Hiya, we had a new pressurised hot water cylinder fitted a few weeks ago even though its double the size of our last one we are finding we aren't getting any more hot water. So once the tank is full and the immersion has turned off and i touch the tank only the top half feels warm and the bottom half still feels cold. My theory is because the element / thermostat is half way up the tank its only heating to that? which seem pretty crap and a waste of the other half of the tank? basically to where the line is on the picture.