A split system central air conditioner with a Seasonal Energy Efficiency Ratio (SEER) of 16 or higher would likely be the best option for your home.

In a climate as hot as San Antonio’s, it’s very important to have an energy-efficient air conditioner. The SEER rating indicates the level of efficiency and although we recommend 16 as the minimum because it will qualify you for the federal Residential Energy Efficiency Tax Credit, the higher the SEER rating, the more money you’ll save in the long run.

Air conditioners made in the ‘70s, like your current system, could only have had a maximum SEER rating of eight. This means, you can essentially cut your cooling costs in half by upgrading to a new system. As you upgrade your central air conditioner, you’ll want to upgrade your ductwork as well, especially if it hasn’t been done in 35 years. To do this, it’d be a great idea to get an in-home energy audit.

An energy audit will find any leaks in your ductwork so you can seal them up to make your system more efficient. The audit will also identify any leaky areas in your home and seal them up so the air you pay to cool doesn’t seep outdoors. An energy auditor will also be able to analyze your home in order to fit your home with a properly sized system. HVAC contractors commonly size home’s with systems that are too large in order to ensure that they cool the home, but this causes an A/C to cycle more often and ultimately waste a lot of energy.

While all of this information is a lot to consider, an energy auditor will be able to walk you through the steps to picking out the right air conditioner for your home. For more information about energy audits, check out our energy audit topic page. Also, check out CPS Energy’s Residential Energy Efficiency Rebate Program to find out if you qualify for their air conditioner rebate.

Updated July 27, 2010