There is a set of fixed valve combinations before and after the water pump. A shut-off valve and a filter are installed before the water pump. The shut-off valve is responsible for cutting off the system during maintenance, and the strainer is responsible for filtering the medium in advance to prevent impurities from clogging the water pump. The rubber expansion joint reduces vibration, noise and compensates for installation deviations.

A check valve and a gate valve are usually installed after the water pump. The check valve prevents backflow in the pipeline when the water pump stops, which could damage the water pump. The shut-off valve is also used only when maintenance is required. A flexible joint should be installed at the outlet of the water pump first to reduce the vibration and noise of the pump and the impact of vibration on the valves. Then a check valve is installed before the outlet valve to facilitate water cut-off for maintenance. When the water pump stops, the sudden change in pressure in the pipeline may cause backflow, which may cause the water pump impeller to reverse, resulting in mechanical damage or shaft breakage. Therefore, a check valve must be installed at the outlet of the water pump to protect it. A gate valve or butterfly valve is installed at the outlet position, depending on the size of the pipeline diameter.

It is recommended that the installation sequence be as follows: water pump outlet, flexible joint, pressure gauge, check valve, gate valve or butterfly valve.