High operating costs on my Rheem water heater
I have a Rheem tank type water heater, 8 years old, that is expensive to use now. Water heater is located in my garage and the operating cost (energy consumption) increased. As I know I didn't use more hot water than before, the fuel price didn't change, but my monthly bill is 20% higher.
What is going on? Is it time to change my water heater or there is a simple solution?