AVG Solar Non Return Valve High Temperature HTCV15F15C 15mm is a high temperature non return valve designed to prevent the back flow of high temperature hot water. High temperature non return valves need to be installed to prevent high temperature hot water from the solar collector panels damaging plastic water pipes, pumps, valves and other components within the plumbing system. This valve is suitable for pumped solar flow and return lines to prevent back flow. To prevent back flow and damage to the plastic cold water pipe work the HTCV can be installed into the incoming mains supply line to a storage hot water heater.