June, 2009 Issue

Tuxedo Air completes first Arizona pool-powered AC

Jayme Cook
HVACR Today

The Southwest has plenty of two things—sun and swimming pools. So when Bill Sund, a former Carrier employee, moved from Minnesota to California he began devising a plan: a geothermal air conditioning unit, powered by the heat in the ground, that uses a swimming pool to transfer the heat in and out of the ground. “It’s not a new concept,” said Sund. “The thing that is new is using the swimming pool as a heat sink.”

“In Minnesota, we’d been putting in geothermal water source units using ponds, streams, lakes and creeks. When we got to California, I just thought, WOW, look at all these swimming pools. So I started investigating how the pool works, the temperatures and performance. But we never got into the mode of doing that there. In California, land is like gold, so no one wanted us to dig it up and put a loop in.” Sund moved to Arizona in 2004 and later opened Tuxedo Air, LLC in Gilbert in 2005. It was in Arizona that, after 20 years of explaining and pitching his idea to apprehensive parties, he was finally able to install a working prototype at a residential home.

Sund installed the unit at a home in Queen Creek and says it appealed to his client since the unit runs off geothermal power and it is energy efficient and cost effective.

“The machine itself is a standard Bryant Geo unit. I just retrofitted the pool to make it work,” he said. “It uses the water from the swimming pool as a direct condenser for the heat pump and as the heat builds up in the pool, it soaks back into the ground,” Sund explained. “Around here, the ground is about 74 degrees around six or seven feet deep. People are apprehensive about this because the national average ground temperature is lower.

Sund said that currently the unit is running with an EER (Energy Efficiency Ratio) of 24, which he said is double the results that anyone else on the market currently offers, other than a water-source heat pump. The best air-cooled machines on the market have an EER of around 13 and the models are showing enormous cost savings in the long term. “Do not confuse EER with SEER,” Sund added.
Sund is monitoring the unit’s performance himself. “I have real-time monitoring on it so I can see when it runs, what the temperature is and how it performs. I’ve got it all set up on site with the exception of a weather station. I’m using the Queen Creek weather station right now to correlate the data. It’s working very well.”

Sund said his client is extremely happy with the geothermal unit. He replaced seven tons of air-cooled heat pumps with a 5 ton, two-speed Bryant water source heat pump and reported it’s doing a beautiful job on cooling the home.

“It has taken a long time for me to develop this. I am a one man army advocating this and I don’t have a lot of resources so it’s taken quite a while to get it all together. The engineering is sound, the application is exactly as Bryant would have it and it’s followed to a T with the most modern and the latest techniques as far as installation practices. When I started it up, it did everything I thought it would do,” said Sund.

There is a renewable energy 30 percent tax incentive plus a Federal $1500 stimulus package available to qualifying clients. Both power companies in the Phoenix area are offering rebate programs for high efficiency systems. “There is no down side when the system qualifies for installation,” commented Sund.