Leaking Sprinkler Heads: Valve Diaphragm or Low-Head Drainage?

Two sprinkler heads leak after system off. Water flows from supply pipes when heads removed. Valve body sprays water when manually turned on. Valve marked "Hardie."

Two Possible Causes

1. Low-head drainage: Heads at lowest points drain residual pipe water after cycle. Normal—install check-valve heads (Rain Bird 1804-SAM ~$3)
2. Valve leak-through: Diaphragm not sealing. Replace with Irritrol diaphragm (Hardie = Irritrol now)

Diagnosis

• Leak stops after 5-10 minutes → low-head drainage
• Leak continuous → valve diaphragm failure

Valve Diaphragm Source

Hardie valves = Irritrol now. Purchase Irritrol diaphragm kit matching your valve model (stamped on body).