DIY Doctor UK DIY Forums

I am getting hot water from the hot water cylinder backing up into the cold water storage tank. At the same time the fill on the central heating expansion tank is constantly filling. Any ideas?

Hi timce
If your hot water cylinder has been around for a while the most likely cause it that the heating coil has perforated.
Presumably your CH expansion tank is higher than your cold water tank so you can check for perforation by tying up the ball valve in the expansion tank, turning off CH and HW and see what happens to the water levels.
Regards S

Thanks, will give it a try and let you know!

Thank you. Also emptied water from cylinder and could hear water from hole in cylinder spraying against the inside of the cylinder!! New one being installed today!