Ok, As I always do, I am putting up a repair problem here before calling a professional.

 

I have a new hot water heater (only a year old).  It is a 6 year model.  Sometimes the water is only lukewarm when it comes out in the shower, other times it is border line hot.  Sometimes we only get 15 minutes of hot water (which causes a problem for my wife since I usually shower first) and other times it seems to pump out hot water for a long time.  

 

Question.  Is there some kind of setting I can adjust to fix the fact that it is only producing 15 minutes worth of hot water sometimes.  I used to live in a condo with a hot water heater half the size and we never ran out of hot water.

 

or...

 

Do you think I need to call someone?

 

Note:  I am OK at fixing things...I stress OK.

 

Thanks in advance.

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