Starway - Viton O-Ring 37.7 × 3.53 mm 90 Shore A for Automatic Backwash Valve - 7039415

Starway – Viton O-Ring 37.7 × 3.53 mm 90 Shore A for Automatic Backwash Valve

This is a genuine Starway replacement Viton O-ring (inner diameter 37.7 mm, cross-section 3.53 mm, 90 Shore A hardness) designed to maintain a leak-free seal inside the Starway automatic backwash valve. Keeping this sealing element in perfect condition is essential for reliable, pressure-tight operation of your pool’s automated sand filter system.

Compatibility

This O-ring is a direct replacement part for the Starway motorized automatic backwash valve (type reference 4150/4152). The Starway valve is a motorized 5-way valve used for the automatic reverse flushing of pool sand filters, available in Ø 50 mm and Ø 63 mm pipe sizes. Always verify your valve’s part reference before ordering to ensure correct fitment.

Why Genuine Viton Matters

Viton (FKM) is a high-performance fluoroelastomer chosen for its superior resistance to pool chemicals, chlorine, and temperature fluctuations. At 90 Shore A hardness, this O-ring provides a firm, durable seal that resists compression set over time — minimising the risk of leaks and pressure loss during both the filtration and backwash cycles. Using a genuine Starway part ensures dimensional accuracy and material quality matched to the original valve design.

Installation

Replacement of internal valve seals should be carried out by a qualified pool technician. Always isolate the valve from the power supply and close the water inlet before disassembly. Lightly lubricate the O-ring with a silicone-based grease before fitting to ease installation and extend seal life.