Pentair 40mm Hydrostatic Valve – Pool Safety Pressure Relief Valve

Pentair 40mm Hydrostatic Valve – Genuine Replacement Part

Protect your pool structure from groundwater damage with this genuine Pentair 40mm Hydrostatic Valve (Part #5132500). Designed as a direct replacement for pools using 40mm fittings, this safety valve automatically releases excess sub-pool water pressure — the primary defence against pool pop-out, floor heaving, and wall cracking after heavy rain or rising water tables.

Why Replace Your Hydrostatic Valve?

Hydrostatic valves typically last 5–6 years. Over time, pool chemicals degrade the valve seal and O-ring, calcium build-up can seize the valve open, and spring failure prevents correct operation. A failed valve puts your entire pool shell at risk:

• Pool walls can deform and split
• Pool floor can hump upward and crack
• In severe cases, the entire pool shell can lift out of the ground

How It Works

When groundwater pressure builds beneath your pool — for example during a storm or after heavy rainfall — the hydrostatic valve opens automatically, releasing water harmlessly into the pool interior. Once pressure equalises, the valve closes and reseats. This simple but critical mechanism keeps your pool shell stable and in the ground.

Product Specifications

• Brand: Pentair
• Part Number: 5132500
• Fitting Size: 40mm
• Weight: 0.2 kg
• Compatibility: Standard 40mm pool floor fittings
• Condition: New / genuine Pentair part

Frequently Asked Questions

How do I know if my hydrostatic valve has failed?
Signs include visible water seeping up through the pool floor drain, the drain cap being pushed upward, or unexplained water appearing in the pool after rain. A plumber or pool technician can confirm with a pressure test.

Can I replace the hydrostatic valve myself?
The valve is located in the main drain at the bottom of your pool. Replacement typically requires draining the pool and is best performed by a licensed pool technician.

Is this valve suitable for both concrete and fibreglass pools?
Yes — hydrostatic valves serve the same function in both pool types, provided the fitting size matches (40mm).

How often should a hydrostatic valve be replaced?
Every 5–6 years as a precaution, or immediately if signs of failure are present.