This is an odd one, read previous similar posts but nothing quite fits.
Have a 3 coil cylinder, rayburn solid fuel convection, central heating pumped and solar coil pumped. With the boiler off, rayburn in and solar off the main cold water storage tank keeps overflowing. If I shut the gate valve off from the tank to the bottom of the cylinder the expansion pipe drips - so I know I have a problem in the hot water circuitr. However, both header tanks for the rayburn and boiler are lower than the cold water tank. Why would a hole in the coil push water up into cold water cistern and not into the relevant independent header tank. It doesn't make sense to me.
Any ideas what is happening? I'd say it was definately a hole in a coil except that the cylinder was new 2 years ago. Problem has been steadily got worse. What else could it be?
Thanks for your time
Have a 3 coil cylinder, rayburn solid fuel convection, central heating pumped and solar coil pumped. With the boiler off, rayburn in and solar off the main cold water storage tank keeps overflowing. If I shut the gate valve off from the tank to the bottom of the cylinder the expansion pipe drips - so I know I have a problem in the hot water circuitr. However, both header tanks for the rayburn and boiler are lower than the cold water tank. Why would a hole in the coil push water up into cold water cistern and not into the relevant independent header tank. It doesn't make sense to me.
Any ideas what is happening? I'd say it was definately a hole in a coil except that the cylinder was new 2 years ago. Problem has been steadily got worse. What else could it be?
Thanks for your time