Originally Posted by armye7
I have 3 valves located behind the hot water heater, I have to get under the coach to get to them. Dealer says the middle must be closed and the top and bottom one must be open.
The dealer is correct. You should also check your outside and showers.
If the faucets are both on and the handle is closed, it will allow hot water to mix with cold water when demanded from any faucet.
My hot water is VERY hot so there is something going on with your heater.
You could also have a bad high limit switch.
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