running out of hot water

[lifetreasure]

I have to keep turning the cold down. I have replaced the dip tube and the thermocouple. Is there something I am over looking? It is a gas water heater. Thanks

[DUNBAR PLUMBER]

Need more info about water heater such as:

# of gallons

How old

Brand name/manufacture

What type of water lines leading to tank

# of gallons of hot water before going cold

and

is it only being noticed in the showers.

[noroomsforme]

Turn the temp up to 140 take water temp when the burner cuts off see if temp is right. Has the performance changed in last 6 months of use? Maybe the burner is dirty?