3 things come to mind: Is there a tempering valve in your plumbing system?
Is it possible that there is a dripping hot water faucet or maybe some kind
of appliance valve (washer, dishwasher?) and, what kind of showerhead does
your shower have? Have you tried a limited-flow showerhead?


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Make it as simple as possible, but no simpler.

Larry Wasserman - Baltimore Maryland - lwasserm(a)sdf.lonestar.org