This question sounds a bit crazy to me but after all the years living
in our home (since new in '98) I've decided to ask.
My wife and I live in a house with 2 gas hot water heaters (2 story
house). We've noticed since we lived in the house that on milder days
the hot water from the shower heads doesn't feel as hot as when the
outside temperatures are colder. I don't think it's our imagination
because we notice the position of the hot/cold water handle of the
shower (it doesn't vary a lot but I think you can see a difference).
This doesn't seem to be the case tho for the faucets else where in the
house.... they always put out hot water when the hot water is turned
Do the shower heads or its plumbing have some kind of sensor for
regulating how hot the water will come out based on surrounding
temperatures? Seems overall to me to be a good feature if even I'm
losing my marbles.