How to Fix a Sand Filter Multiport Valve?
- Leaking around the outside of the top it may be the cover o-ring (6) that needs replaced.
- Water is leaking from the backwash line / port then it is usually the spider gasket (8) that needs replaced, sometimes the spider gasket (8) and the rotor (4) are one part.
- Please see below for a guide on replacing spider gaskets.
It is important that your valve on top of your Sand Filter operates easily and properly, every 5-10 years, the spider gasket will need to be replaced.
If your losing water a worn gasket in the valve may be the source of the leak, check your backwash line for leaks.
Check the spider gasket by removing the top of the filter.
First turn the pump off, and release all pressure from system
Place the selector handle at the "winterise" position
Remove the screws from the lid (1) and lift off by the handle
Remove old gasket (8), if it has been glued in remove all remaining glue with a small screwdriver and clean the groove completely or the new gasket will not seal.
There are differing thoughts when it comes to glueing the gasket in if you do decide to use a gasket glue, use very sparingly place tiny dabs of superglue or silicone (or any gasket adhesive), into the grooves.
Minimum cure time is 2 hours. Curing for 24 hours is recommended for full strength.
Replacing the Key Assembly
An easy way to fix problems with the handle, lid or rotor is to replace the whole top assembly, as it is already assembled you just need to remove the cover screws and pop the new one in place.
Replacing a Multiport Valve:
If your valve has a valve body that is cracked or has a number of problems then you can just replace the complete Multiport Valve (MPV).