The answer to 'air handler high energy bills' is that there are several common causes, including a dirty air filter, leaky ductwork, an oversized unit, or a malfunctioning thermostat. Symptoms may include uneven cooling, frequent cycling, and high energy usage. Solutions can range from simple DIY maintenance to more complex repairs or replacement, depending on the root cause.
If the air filter is dirty, replace it. Seal any visible leaks in the ductwork. Check that the air handler is the proper size for your home. And ensure the thermostat is functioning correctly and properly programmed. For more complex issues, it's best to call in a professional HVAC technician to diagnose and resolve the problem.