The answer to 'why is my water heater high energy bills' is that there are several common causes, including a malfunctioning thermostat, sediment buildup, or an aging or inefficient water heater. These issues can lead to the water heater working harder and consuming more energy to heat the water, resulting in higher utility bills.
Some common symptoms of these problems include inconsistent water temperature, strange noises from the tank, and the water heater running more frequently. Potential solutions include adjusting the thermostat, flushing the tank to remove sediment, or considering a more energy-efficient replacement water heater. If you're not comfortable troubleshooting the issue yourself, it's best to call a professional HVAC technician to diagnose and repair the problem.