It shouldn't matter which way you turn the handle, however a bunch of 'pool pros' say to do it only one direction.(I was taught this at the same time I was taught to only use 'pool store chems' and that bleach is bad for a pool) A properly lubed and maintained multiport doesn't need that. I think what they're trying to avoid is the 'spider' or 'wagon wheel' gasket unseating or tearing. I've found this to be a 'non issue' as long as the multiport is properly cared for.
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