HVAC technician invents an instrument to test pressure switches in furnaces and goes entrepreneurial with it
By Tom Gibson, P.E.
Rich McFarland has worked in the HVAC Industry for 30 years as an installer, service technician, and manager, and he has owned heating and air conditioning companies. “In my background, I trained mostly from the military — schematics, electronics,” he reveals. “I’m not an engineer per se, but I am an engineer at heart. I’ve been inventing stuff all my life.”
This eclectic mix of skills has led McFarland, 59, on a parallel path to engineering and set the stage for him to parlay his knack for inventing to becoming an entrepreneur marketing a product he developed. Good Day Tools, a new company in Cincinnati, Ohio, has started production of its Draft Simulator, invented by McFarland and co-owner Gene Warren. Along the way, McFarland has made the business a family affair, as Gene is his son-in-law and son Matt works as an IT person and bookkeeper.
The trio predicts the device will have major implications in the world of furnaces and boilers. There may be a few naysayers, but McFarland reports, “it has been extremely well received. It’s just unbelievable. We’ve gotten a lot of kudos across the United States. It’s grown fast in popularity.”
Just what is a Draft Simulator? The hand-held, battery-operated instrument can calibrate adjustable pressure switches and test switches, procedures that until now involved crude tests such as the breath test and using a syringe to simulate vacuum. The instrument produces a sustainable vacuum pressure from 0 to 100 inches of water column with the twist of a knob. This allows HVAC technicians to simulate the pressures draft inducers produce on induced draft furnaces while determining when pressure switches open and close, all without a furnace running. To use the Draft Simulator, you connect cables and hoses from the instrument to the pressure switch and a digital manometer, which measures pressure. This can be done with the switch mounted on or separate from the furnace.
A furnace pressure switch, which has a diaphragm and microswitch inside, serves a safety function by sensing pressure inside the furnace and only letting electric current flow when the pressure is normal. If the pressure should reach a dangerous level, the switch will shut off the electrical current to prevent damage. As an example of what can happen, if a furnace runs while the flue or heat exchanger is partially blocked, carbon monoxide poisoning or a deadly fire can result. Furnaces may contain several different types of pressure switches in residential, commercial, institutional, and industrial applications.
“I’m a military brat. I grew up everywhere. I was born in El Paso, Texas,” McFarland says in detailing his background. He too went in the military. “I was trained in aviation ordnance, so we built bombs and missiles. Had a great time with that.” After that, he attended San Bernardino Valley College in California for heating, air conditioning, and refrigeration. He didn’t stay the course, though, because he was young and married, and he ventured east and got his first job in heating and air conditioning in Virginia. He went to various other schools and got on-the-job training. He owned two companies, Alpine Heating in Cincinnati and All Seasons in Portsmouth, Ohio, and also worked for other companies.
Design Arises from Frustration
Work on the Draft Simulator started in 2003 when, McFarland recalls, “I became frustrated with the number of pressure switches we had. We had at least 50 pressure switches on our truck, and it took up a lot of space. It never failed; you’d always have the wrong one.” Working with a couple of local HVAC supply warehouses, he determined that there was no way to set a universal pressure switch. “So I thought, ‘there’s got to be a better way.’ I started designing a device to calibrate adjustable pressure switches.”
With co-owner and co-inventor Gene Warren looking on, McFarland demonstrates the Draft Simulator on a furnace.
Gene Warren got involved then, helping McFarland with the design. An auto mechanic who worked a short time at Ford Motor Company, Warren is mechanically inclined and proved instrumental in developing the tool. Work took place in their shop and Gene’s basement.
“We actually started with an aquarium pump and reversed it to create a vacuum.” McFarland says in recalling their design methodology. “We had to regulate that flow, as that is the most important part of the tool.” This allows you to maintain pressure, which is hard to do when you’re drawing a vacuum. “It was trial and error to figure out exactly the right size tubing, connections, orifice, and everything inside to get this to work right. It took quite some time.”
McFarland was working for Potts Heating and Air at the time, and he and Gene approached his boss Bill Potts to demonstrate the tool and see if he wanted in on the action. They needed someone to pay for their venture, and Potts said yes, so they started looking for ways to build and sell the tool. They hired an attorney and started patent procedures.
With the concept proven, designing the Draft Simulator for production became a daunting exercise in juggling all the components, often against cost. This included the pump, enclosure, valve for adjusting airflow, and batteries. They tried units with and without a digital manometer built in, finally settling on a design without it. “It’s funny, every time we feel like it’s going to sell or work out, it fails. At times, we gave up and tried to put it to bed, but this thing has a mind of its own,” McFarland says.
Having accomplished the next level of design, McFarland and Warren set out to sell their concept to a tool manufacturer, approaching several in the process. Some would express interest at first but then back out later for various reasons. One manufacturer required that they buy 1000 units. Bill Potts was tapped out, having invested over $30,000 trying to get this up and running. Then they met another investor. They found a company near Cincinnati to manufacture the units, and McFarland points out that most of the parts are made in the United States, including the molded plastic housing.
Offers Several Advantages
In telling what the Draft Simulator offers, McFarland explains, “You will always have the right pressure switch, even in the middle of the night. You can reduce inventory by stocking just adjustable pressure switches and a few OEMs for the warranty furnaces.” He continues, “Pressure Switches are the most misdiagnosed controls in today’s furnaces. In fact, we had one manufacturer of furnaces state that over 90 percent of pressure switches returned under warranty tested fine. You consider that quantity, we’re talking millions of dollars in loss with pressure switches.” HVAC contractors and wholesalers can save time and money in the entire supply chain by reducing callbacks and finding faulty pressure switches that appear to work fine.
While most pressure switches can be adjusted, they are only meant to be factory pre-set to a particular brand of furnace. “You could have dozens upon dozens of OEM pressure switches. It’s a nightmare stocking all these or going to get them,” McFarland says.
A truly adjustable, or universal, type of pressure switch does exist, but it is only meant for emergency use. You can install one in the middle of a cold night for the furnace to run, say, until you can come back and replace it with the right switch. McFarland says this can be dangerous because you don’t know exactly what pressure you set the switch for. With the Draft Simulator, you can set the switch exactly where it’s supposed to be and forget it. You don’t have to come back. “You can now use an adjustable pressure switch like a regular preset switch because you can set it accurately.”
Pressure switches commonly see use on induced draft furnaces. A furnace draft inducer blower is a relatively new component of modern furnaces that became part of heating units after the government mandated efficiency standards. A typical draft inducer blower lies in the gas burner compartment of a furnace and consists of a motor-driven wheel assembly or fan. The flame originates at the burners and is drawn into the heat exchanger by the negative pressure produced by the draft inducer. A pressure switch attached to the draft motor by a small tube senses the negative pressure created by the draft inducer. By improving the quality of air moving through the furnace, the draft inducer blower helps improve efficiency of the system.
McFarland and his partners got a patent on the Draft Simulator three years ago and lined up an investor last year. They’ve attended a host of trade shows to spread the word about it. A handful of supply houses in the United States and Canada carry the Draft Simulator, and they’ve gotten interest from other countries.
In reflecting on the process, McFarland says, “It’s very exciting to see something come to fruition, especially when you look back to nine years ago, on the drawing board, sitting there trying to figure out how to make it work.” With his ex-boss Bill Potts as one of his partners, McFarland now concentrates fulltime on his entrepreneurial endeavor, hoping to reap the rewards and leave a big mark on the HVAC industry.
For more information on Good Day Tools and the Draft Simulator, visitGoodDayTools.com