对于现代家庭，热水器是必不可少的物品。近几年来，热水器的品种也不断推陈出新，从快速直排式到容积式，从用气到用电，人们的选择也越来越多。 从市场上看，目前的流行趋势是容积式热水器。这种产品的优势在于具有储备功能，不会因突然停水而断流，也免了因气小或断电而遇到 For modern families, water heaters are essential items. In recent years, the variety of water heaters have also been introduced, from the rapid in-line to volumetric, from gas to electricity, people’s choices are more and more. From the market point of view, the current trend is positive displacement water heater. The advantage of this product is that it has a reserve function, does not stop due to a sudden water stop, and also avoids encountering