See the SuperCool Slide Rule Made in San Angelo

SAN ANGELO, TX — An idea laboratory is how one owner describes his San Angelo business. In a room full of patents, Bryan Knowlton invents, makes prototypes on 3-D printers, and when the prototype shows promise, he may send the computer file defining the 3-D model to a factory for mass production.

Knowlton’s most successful invention is the “SuperCool Slide Rule,” a pasteboard apparatus that allows HVAC technicians to figure and calculate any challenge facing them when on the job repairing or replacing HVAC systems.

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Above: The SuperCool Slide Rule. On the table are free slide rules given by AC companies. Knowlton's slide rule incorporates the features found in free tools, too. (LIVE! Photo/Joe Hyde)

The SuperCool Slide Rule is available online and at Amazon for $19.99. Knowlton sells a lot of them, something close to 50,000 so far. While we were talking recently, he unlocked his iPhone. Four were sold in the past 15 minutes. He is sublime about the success of the slide rule.

In the video below, Knowlton explains the SuperCool Slide Rule:

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“I don’t usually sell that many within a 15-minute timeframe,” he assured me.

Knowlton explained that the market for the slide rule is 2 million HVAC techs worldwide. That’s why he’s transitioning the poster board apparatus into a mobile app for iPhones and Android devices. He already has the prototype on his own phone. The payoff? He can sell the software as a service with an annual service fee of, say, $20.

Multiplied by 2 million technicians, depending on market penetration, that’s a respectable amount of annual recurring revenue.

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Above: Early versions of the SuperCool Slide Rule. Knowlton said the inspiration for the slide rule was aviation’s E6B tool, see mockup behind. Foreground: The first manufactured version. (LIVE! Photo/Joe Hyde)

The HVAC industry is near and dear to Knowlton’s heart. He founded, operated, and eventually sold an HVAC company in five cities in New Mexico before relocating his family from Artesia, then Carlsbad, New Mexico, and finally to San Angelo in 2008.

A traffic jam one afternoon in San Antonio when Knowlton and his wife were visiting while considering relocating there, convinced both they’d rather live in San Angelo than deal with the traffic in a major metro area. The rest is history.

Overall, the magic of the SuperCool Slide Rule isn’t necessarily the product itself. Rather, Knowlton said, it is the content on his website and his website’s high Google rankings for all things HVAC tech. Knowlton has produced hundreds of videos on how to fix air conditioners, and how to use his slide rule doing so.

After selling his New Mexico HVAC business, Knowlton pursued his pilot’s license. He currently holds a multi-engine and instrument rating from the FAA. He recalls one of his first experiences flying a twin. After flying twice in the copilot’s seat in a Piper Seneca, Knowlton told the plane’s owner he’d like to buy it. After the money was exchanged, Knowlton was handed the keys to the plane.

“I flew from Waco to San Angelo, at night,” he said.

With confidence, Knowlton volunteered for Angel Flights using his plane to build up more flight hours.

However, the twin was hard to start on cold days in the morning.

“The engines just didn’t want to turn in the cold,” he said.

That led to Knowlton’s next commercial success that only an HVAC guy with a pilot’s license could imagine. It was a small, portable engine heater. The thermostat-controlled heater marketed on Knowlton’s AircraftHeaters.com can be placed in the engine’s cowling and warm it up on cold days. It’s a dream come true in the more northern regions where it’s colder. But Knowlton says the heaters have great applications in Texas, especially during winter months. “Those engines don’t like to turn over when it’s less than 32 degrees,” Knowlton explained.

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Above: The Aircraft Heater for plane engines next to an example of the high quality case that is included. (LIVE! Photo/Joe Hyde)

Angel Flights, where volunteers ferry medical patients from usually more rural areas to city hospitals, gave Knowlton visibility into the operations of life flight helicopters, similar to Shannon Medical Center’s Airmed1 helicopter ambulance. During the cold months, the interior of the air ambulance needs to be heated. Knowlton’s AircraftHeaters.com provides a three-heater, thermostat-controlled portable brick-sized heater with a heavy-duty three-phase plug to do just that. Knowlton learned through observation and discussions with life flight helicopter crews that his now-competitor’s plug tended to fray easily. Knowlton’s team designed and built a tougher plug and connector.

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Above: Knowlton's heater is also made for boat bilges. (LIVE! Photo/Joe Hyde)

“Made in America!” Knowlton exclaimed.

Knowlton is secretive about his lab that currently employs five with higher wages than the mean in San Angelo. He believes the workforce here is excellent. So much so, he mused about founding a mobile app development company and bringing in more upper-middle class jobs.

Knowlton explained in detail the problems he experienced hiring a competent app development company to help him develop the slide rule app (in Swift, Apple’s iOS development environment).  It was a problem, and for Knowlton, always tinkering, solving problems is the way he and his patent lab moves ahead.