Single or Variable Speed A/C Units?

Basic, single stage systems are less expensive upfront than the variable speed system, but in the life of the system you’ll pay thousands more to CPS/GVEC. The variable speed does cost more upfront (2-3k depending on the tons) in the long-run your investment will pay-off with savings in utilities and the maximum comfort benefits. In addition to using 42% less energy, you’ll get consistent room temperatures, less humidity and better filtration. It will take 2-4 years of energy savings to pay the costs difference between the single speed and the variable speed but after the difference is paid, the rest of the years in operations is money staying in your pocket that your are not paying in utilities to CPS or GVEC.

Here’s an example:

If the single speed system is $10,000 and $2,035 a year to operate, cost of ownership & utilities over 10 years is $30,350.

A variable speed system at $12,000 and $1,300 annual operating costs over 10 years is only $25,000 – Savings of $5, 000 over 10 years. or $9,025 savings over 15 years.

If you want the lowest energy consumption & utility cost and most consistent humidity reduction and comfort, a 16-18 SEER variable speed system is our recommendation.

If you are look for something in the middle, in some climates a two-stage system offers two compressor speeds. In milder climates and in the overnight hours a two stage compressor can initiate at 70%. If the thermostat set point can be satisfied at 70% compression the unit will shut off. If not, the 70% will jump to 100% after about 8-10 minutes. 2 stage compressors are a great technology, but it’s not recommended when climates are extremely hot for most of the year. (like San Antonio, TX)

The Trane XV18 & 20, the Carrier Infinity and the Daikin FIT are our top choices for Variable Speed options.