ASAB S Series - Replacement S1/S3/S7 Prime Valve

The ASAB S1/S3/S7 Prime Valve is the dedicated prime/re-circulation valve assembly for ASAB S1, S3, and S7 airless sprayers. It controls whether material is sent to prime/return (for filling and de-airing the system) or directed toward the spray circuit, making it a key component for smooth priming, consistent pressure, and clean changeovers.

If your unit is slow to prime, won’t hold pressure properly, or you’re seeing material leaking past the valve, a fresh prime valve can often bring the sprayer back to behaving like it should—without the drama.

Key features

• Genuine ASAB prime/recirculation valve for S1 / S3 / S7

• Enables reliable priming and de-airing, helping reduce sputter and pressure instability

• Supports proper pressure control and clean transition from prime to spray

• Ideal replacement if the valve is leaking, sticking, bypassing, or difficult to turn

What’s included

• 1 x Prime Valve Assembly (service replacement)

Recommended replacement
Replace if the valve does not seal correctly, is difficult to operate, or allows ongoing bypass/return flow when set to spray. A prime valve that won’t behave is a quick way to turn a straightforward job into an extended troubleshooting session.

Safety Check

• Relieve all fluid pressure (trigger the gun into a waste bucket and follow the sprayer’s pressure relief procedure) before loosening or removing the valve.

• Isolate power (unplug/disconnect) before servicing any pump components.

• Wear PPE: eye protection and chemical-resistant gloves—especially during flushing and when handling solvents.

• Beware of injection risk: high-pressure fluid can penetrate skin—never check for leaks with your hand.

• Test carefully after install: prime at low pressure first, check for leaks, then return to normal operation.