This timer is built in with a solenoid valve. Technically, all solenoid valves decrease water pressure. If you are not satisfied with the decreased water pressure, please contact customer support.
#3 TIMER VALVE WON’T TURN ON/OFF. RESET THE VALVE:
Remove the battery case and install 4 new AA alkaline.
Keep the dial at ON. Press and hold the OK/MANUAL button and insert the battery case back at the same time.