How do you replace a swimming pool main drain valve?

The valve for the main drain on older pools would be located at or on the equipment pad. You will most likely need a pool tech who knows how to plumb pool equipment to have it changed out.

On the other hand if you mean replacing a broken or loose main drain grate then you would have to take the loose or broken grate to your local pool store for an updated version replacement. They will advise from there.

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