Around 2018 I moved to Croatia but I had owned the house for a while as a renovation project. I designed and installed a solid fuel central heating system. It used pumped central heating with gravity hot water. That design was chosen so the hot water cylinder could act as a heat sink in the event of pump failure or electricity cuts. The problem was, the indirect cylinder never got hot using the boiler, so I had to use the immersion heater all year round. I had bought the cylinder secondhand on Ebay in UK. I used the system for a few years like that but then had a flood. The indirect coil had failed and overfilled the expansion tank for the central heating. I cut up the cylinder to see what had happened. I discovered that the coil was not one fat pipe but several thin ones, This is why it never worked, it was only suitable for fully pumped systems! I could not buy a direct replacement cylinder in Croatia so I fitted an Ariston, mains pressure indirect cylinder. This works fine with the boiler and is also better insulated than the UK cylinder.