Botanic Garden >> Gardening > >> Question and Answer >> Irrigation

Hunter SRC Plus: Old Hardie Valves Won't Open for Winter Blowout

Hunter SRC Plus works with water but 1972 Hardie/Buckner valves won't open for compressed air winterization (80 PSI). 28V at controller, 20 Ohm solenoids.

Issue

Diaphragms hardened with age. Water pressure (40-60 PSI) lifts them; air (80 PSI) lacks sustained pressure to overcome stiff diaphragms.

Solution

Manually open each valve at bleed screw (star-shaped on top)
Turn counterclockwise with air pressure on
Air will flow, valve opens
Close bleed screw when zone clear

Long-term

Replace diaphragms on all 3 valves. 42-year-old rubber is brittle.

Irrigation: Rain Bird ESP-8LXi+ Zone 1 Valve Stays Open: Controller or Wiring Fault?; Lawn Sprinkler Zone Runs Continuously: Valve Diaphragm or Solenoid Failure; Identifying and Replacing a Hardie Hydraulic Valve in an Indexing System; Orbit Valve Won't Open: Check Wiring & Timer Voltage; Toro ECX: System Only Runs with Bleed Valves Open — Replace Diaphragms; Control Valve Won't Shut Off – Replace Valve After Diaphragm Fails; Choosing a Sprinkler Valve for Low-Pressure Tank Drainage; Zone 1 Valve Sticks Open Annually; Hardie Valve Requires Bleed Screw Open for Pressure – Solenoid or Port Issue; New Timer Installed: One Zone Has Lower Pressure Than Manual Operation

Garden Articles

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

Hardie & Lawn Genie Valves Low Pressure: Check Flow Control & Supply

Eliminating Water Hammer and Vibrating Noises in Sprinkler Systems

Hardie 16-Zone Controller Failing: Transformer Overheating, Replacement Options

Zone Works Manually But Not Electrically: Valve Opening Issue

Noisy, Low-Flow Valves: Flow Control Adjustment for Irritrol Valves

Richdel 3/4" Valves: Manual Bleed Test for Pressure Loss

Plants

Nelson Controller: Zone 2 Runs With Every Other Zone — Wiring or Valve Issue?

Fixing a Sprinkler Valve That Won't Shut Off: Diaphragm Replacement

Toro Zone 3 Failure: Controller Voltage Test After Valve and Pump Replacement

Hardie Rain Dial Won't Activate Sprinklers After Rain Shutdown

Water Hammer on Zones 4-6: Downhill Velocity and Residual Water

Sprinkler Zone Won't Shut Off? Troubleshoot a Stuck Valve

Sprinkler Valve Won't Shut Off: Flow Control Adjustment