Certain restrictions create backpressure that may negatively affect the pump and potentially create cavitation that will increase maintenance. Take a minute to inspect the pump and connected piping to ensure there are no visible restrictions. Look for the following at both the pump’s inlet and outlet:
Credit by Michael Sandlin
https://www.pumpsandsystems.com/pumps/october-2016-5-minute-fix-troubleshoot-diaphragm-pump