Hayward Pro Series Sand Filter Tank to Valve O-Ring (20-GMX600F)

Genuine Hayward Pro Series Sand Filter Tank to Valve O-Ring — part no. 20-GMX600F. This large rubber O-ring (item 3 in the Pro Series exploded diagram) seals the multiport valve to the filter tank on Hayward Pro Series and Pro Series Plus sand filters. A worn or cracked O-ring causes water to leak from the joint between the valve and the tank. Replacing this O-ring restores a watertight seal.

Compatibility

Suits Hayward Pro Series Plus and S-series sand filters, including:

• S311SX / S311SXV / S360SX
• S140T / S144T / S164T / S166T
• S180T / S190T / S210T / S220T / S230T
• S244T / S245T / S310T / S310T2
• S210S / S220S / S244S / S310S
• MaxFlo II SP2700X Series Filters

Product Details

• Brand: Hayward
• Part number / SKU: 20-GMX600F
• Position: item 3 in Pro Series exploded diagram (tank to valve O-ring)
• Material: rubber
• Genuine Hayward spare part

Frequently Asked Questions

How do I know if this O-ring needs replacing?

If water is leaking from the joint between the multiport valve and the top of the filter tank, the tank to valve O-ring is the most likely cause. Turn off the pump and relieve system pressure, then remove the multiport valve and inspect the O-ring for cracks, flattening, or deformation. Replace if any damage or deterioration is visible, or as part of routine filter servicing.

Does this suit all Hayward Pro Series sand filters?

Part 20-GMX600F suits a wide range of Hayward Pro Series and Pro Series Plus S-series models as listed above. If your filter model is not listed, contact us with your filter model number to confirm compatibility before ordering.

Should I lubricate the O-ring when fitting it?

Yes — apply a small amount of silicone-based O-ring lubricant (not petroleum-based grease) to the O-ring before fitting. This helps the O-ring seat correctly and extends its service life.