Capillary thermostat, also known as liquid expansion thermostat, is made based on thermal expansion and contraction principle. The WYG capillary thermostat,with adjustable operating temperature, is designed for temperature control. Its quick response can well prevent the unacceptable heat of water heaters, and guarantee people’s safty. WQB series capillary thermostat is often used as a thermal protector in electric water heaters. The WYG and WQB combination is a good TCO solution for water heaters.