5. When installing the water heater inlet and outlet, the inlet valve and the intake valve must be considered and installed in the corresponding position. 6. When installing the hot water pipe, pay attention to the difference between the water inlet and the water outlet of the water heater, the water inlet is connected to the main valve, and the water outlet is connected to the bathroom pipe. After installation, first open the valve to confirm that there is no water leakage, etc. Finally, install the faucet, shower, etc. in the bathroom. The shower hose height is between 1.8m2.1m. 7. It is the pressure measurement process of the installation of the toilet water pipe: before the pressure test, the valve of the water meter should be closed, the end of the pressure test pipe should be sealed and the water should be injected slowly. After the water is filled, the seal is checked, and then the pressure is manually increased. The pressure drop within the hour is not more than 0.05 mpa.