Connection diagram of water heater and circulation pump

The following two pictures are installation diagrams of the air-energy hot water circulation system:

The first picture omits the return pipe part, while the second picture does not omit it and is more complete. , the clarity is not enough, but it can be basically recognized. The main difference from the first picture is that the water outlet and return water pipelines are complete: such as booster pump, stop valve, various water points, return water pipes, etc.

Electric heating, solar energy, etc. are similar to this and can be used in combination.