Sprinkler Pump Runs but No Pressure – Common Causes

After replacing a sprinkler pump, zero pressure usually stems from one of two issues:

If Pump Runs but No Pressure

• Air leak on suction side: Check all fittings, foot valve, and suction pipe for leaks. Even a small leak prevents priming.
• Pump not primed: Fill pump casing with water before starting.

If Pump Won't Start

• Wiring/relay issue: Check relay between controller and pump. Verify 24VAC at pump start terminals when zone activates.

Quick Test

Manually bleed a valve to confirm water supply is on. Then reset controller (unplug 5 minutes) and reprogram.