Sand Filter change schedule

I have a Pentair Tagelus 145241 Sand Filter (mfg 12/07) that probably needs a spider gasket change (dripping from the waste water piping), but I am thinking of changing the sand too. How often should the sand be changed? And what part# do I need for the Spider Gasket?

The life of the sand depends on a few variables, but on average we say 5-7 years. It’s a good sign that the sand needs to be replaced if you backwash the filter and the pressure on the gauge doesn’t drop. If you don’t have a pressure gauge, you can add a flowmeter to the line and see if the flow improves after backwashing. Sometimes, it’s obvious enough that the flow has improved by looking at the return jets or water features.

We’ll assume you have the 1.5" multiport valve on the filter. You can confirm that by counting the screws that secure the top assembly to the base of the valve. A 1.5" multiport has 6. If you have the original Pentair 1.5" valve. the spider gasket is not available separately. It is glued into the top valve assembly or the diverter. The top valve assembly is much easier to replace.

Top Valve Assembly - Part Number PL0748

Diverter  - Part Number PL0742

Top Valve Assembly

Diverter