Kandyknipe

To run an efficient HVAC, you must ensure your house is fully insulated.
First, check into your attic to find out if you have the right kind of insulation and enough of it.

When you are looking to buy a new air conditioner, consider your climate.
If you live in a hot, dry area, then an evaporative cooler will be your best bet.

When your contractor comes to fix your unit or install a new one, he should walk around your home and investigate what's going on with your current set-up.

Keep your condensers free of nearby obstructions.

Keep plants, fencing, even bushes back and away from the unit.