Filtration spare parts

Silica sand coming out through the return jets indicates that one or more laterals at the bottom of the tank are broken. When these filter slots crack due to material fatigue or excess pressure, sand grains pass through the physical barrier and return to the pool. To fix this problem, empty the filter media, inspect the central manifold, and replace the damaged slotted arms with parts that have the same thread pitch.

Also check that the base gasket and upper diffuser have no play. If the entire tank is deformed due to excessive operating pressure, it is best to replace the unit with a dedicated tank, such as the Starpool Ø400 mm pool sand filter without pump, with multiport valve, to ensure the circuit is watertight.

The key criterion for selecting filtration replacement parts is checking the external and internal thread measurements of the system pipes. Installing the wrong size can restrict flow or cause immediate leaks due to misalignment.

• 1 ½-inch connections: standard for pipes with a 50 mm outside diameter, commonly used with pumps up to 0.75 hp and flow rates below 10 m³/h.
• 2-inch connections: required for 63 mm pipes, designed to handle high flow rates and reduce pressure loss in high-power circuits.
• Metric or imperial thread: check whether the fitting requires a flat gasket or Teflon tape to ensure a completely watertight seal under pressure.

Always check the technical specifications for the original multiport valve before finalizing your purchase of a replacement part.

A continuous leak to the drain outlet while in filter mode indicates irreversible wear of the selector valve's internal spider gasket. This rubber gasket separates the internal ports in the valve head; when it deforms or gets pinched, it allows pressurized water to flow unintentionally into the waste manifold during daily operation.

In most cases, it is enough to replace the glued gasket or the internal deflector assembly. However, if the outer body has cracks from freezing or chemical wear, it is more cost-effective to replace the head with an original replacement part such as Hayward's 6-way 1½" selector valve (SP0710X62E), which restores flow distribution without loss of flow rate in 2026.

The technical difference lies in the selector valve's mounting point and access to the inside of the filter tank.

• Top-mounted or top valve: screws or bolts directly onto the top opening of the filter, saving space in smaller equipment sheds but requiring the pipes to be dismantled to replace the sand bed.
• Side-mounted or side valve: attaches to the side of the tank via two separate ports, making it easier to open the top of the filter without disturbing the plumbing.
• Hydraulic maintenance: side-mounted models offer less resistance to water flow, reducing pressure loss in the system compared with compact vertical configurations.

Always purchase the variant that matches the original pipe layout to avoid structural modifications to the PVC.

A fixed reading above 1.5 bar indicates severe clogging of the filter media, a jammed pressure gauge mechanism, or a blockage in the upper diffuser. If, after backwashing and rinsing, the needle remains still with the pump off, the pressure gauge has lost its internal calibration and must be replaced immediately to prevent false readings from masking dangerous overpressure.

If the pressure gauge works correctly when the power is off but the pressure rises rapidly when the pump is switched on, the filter bed has become compacted due to calcification. In small filters with a compact pump, such as Starpool's Star 300 Sand Filter with Pump, replacing the filter media or bleeding residual air through the lid resolves backpressure issues.

O-rings and elastomeric seals should be replaced every two or three operating seasons to prevent air from entering or water from leaking. Constant exposure to chemicals and temperature changes hardens the rubber, causing it to lose elasticity and compromising the watertightness of the filtration circuit.

Laterals and manifolds have a service life of around five seasons, at which point it is recommended to inspect them when replacing the silica sand or glass filter media. Pressure gauges should be checked annually at the start of the swimming season; any abnormal fluctuation or failure to return to zero when the motor is stopped means they must be replaced immediately for operational safety.

Continuous loss of prime is caused by air entering through a faulty seal in the pump's pre-filter lid or suction fittings. Carefully inspect the O-ring on the clear lid; if it is cracked, flattened, or lacks neutral silicone lubricant, the system loses its vacuum and the impeller loses prime.

Another common failure point is the lower drain plug on the pump body, whose small gasket often deteriorates after winterization. For installations with compact pumps such as Saci's Optima Pump 0.25 HP Single-Phase, replacing these elastomeric gaskets restores suction performance without needing to replace the motor assembly.