Abstract : the water - saving solar hot - water heater is improved . the replacement of the two - position water and vapour valve of the water - saving solar hot - water heater by the two position automatic prot ection valve leads to the transition from hand to automatic protection 文摘:用自动保护双位阀替代节水太阳能热水器的通水输气两位阀，使节水太阳能热水器从手动保护过渡到自动保护，改进了节水太阳能热水器系统
