If I have bad central air, will a window unit lower my electricity bill?
Have you been keeping up on routine maintenance for your unit? (changing the filters on your indoor unit, cleaning your outdoor condensing unit, keeping it clear of leaves and other debris). Also, have you recently had the unit serviced? Not properly maintaining the system will cause a degradation of performance. You will want to definitely keep up on maintenance and have it looked at by a professional to make sure its operating properly. The answer to your actual question is: Maybe. If you buy a small 10k btu window unit, it will most likely give you 10k of cooling more efficiently then your current unit due to the age of your existing system. Based on the information you provided it sounds like on most days your house stays at 82F, but your setpoint is much lower, at like 76F (correct me if i’m wrong) When there is a difference in the space temperature and the unit setpoint the unit will run continuously to meet that setpoint, if you add only a 10k unit, chances are that the addition
