| 摘要 |
PROBLEM TO BE SOLVED: To provide a storage water heater that obtains improvement in the efficiency of a water heater by bath heat recovery and obtains suppression effect on loss of energy in boiling and besides, hardly brings about degradation in the assemblability and rise in the cost due to increase in the components.SOLUTION: A storage water heater includes a hot water storage tank 3, water supply piping 7 connected to a lower part of the hot water storage tank and a water source, a heat exchanger 16 exchanging heat between hot water held in the hot water storage tank and hot water of a bath, a four-way valve 9 switching flow passages between the hot water storage tank and the heat exchanger, storage tank upper piping 11 connected to a hot water storage tank upper portion and the four-way valve, expansion water drain piping 10 connected to a pressure relief valve 14 and the four-way valve, reheating heat source circulation piping 12 connected to an intermediate portion of the hot water storage tank and the four-way valve, and heat recovery piping 13 connected to a downstream side of a pressure reduction valve of the water supply piping and the four-way valve, and further includes a control part which controls switching of the four-way valve between a first low passage configuration and a second flow passage configuration. |
