What is the small period of waterway reconstruction?

Large circulation and small circulation are two return pipe arrangements in hot water circulation system. The big cycle is to connect the hot water pipes of all water points in series, connect the hot water pipes of each water point, and connect them in branches, one by one. Hot water can only flow back to the water heater for heating when it reaches the farthest end of return pipe. Small circulation means that the return pipe is connected to the main water inlet pipe of each room, and only two water pipes (1 cold water pipe and 1 hot water pipe) will appear at the water consumption point, and all backwater will be connected to 1 return pipe at the top.

The advantage of large circulation is easy to use, but the disadvantage is that it takes up a lot of space and needs to reserve more space to install pipes. The advantage of small circulation is that it takes up small space, but the disadvantage is that it takes 2-3 seconds to use hot water.