Originally Posted by LHaven
Amusing related anecdote: where my son lives in the Phoenix Valley, he actually turns his water heater off every summer so he can have a source of COLD water for the house. His cold water faucet delivers consistently hot water from the street feed, and his hot water faucet delivers cold water from his indoor water heater tank.
We live in a rv resort between Phoenix/Tucson that their water storage is in large stainless storage tanks & this time of year the the cold water is hotter than the heated hot water & do as he does, use the water heater to cool it down.
If it's not the outside shower, check the water heater bypass, maybe it's not completely closed.