Destination: Excellence

July 1, 2005
It took one phone call from a customer who wanted Sigman to install the comfort system at his new home.

By Ron Rajecki
executive editor

The Bohn home is comfortable both inside and poolside thanks to Sigman Heating & Air Conditioning. Just ask the Bohns' daughter, Lindsey.

The tiled floors in the foyer and throughout the first floor are heated by a geothermalpowered-radiant system

Sales Manager / "informant" Joel Sigman is the public face of the team at Sigman Heating & Air Conditioning

The home's mechanical room shows Sigman's attention to detail.

There's an old saying that flattery will get you anywhere. But how much flattery would it take to get you to accept an installation job that was 90 minutes away from your office? In the case of Sigman Heating & Air Conditioning, it took one phone call from a customer who wanted Sigman to install the comfort system at his new home—even though the job took Sigman's teams from the company's headquarters in Belleville, IL across the mighty Mississippi to Farmington, MO—a distance of more than 70 miles one way.

"I have to admit that when I made the first trip out there, I had to stop and check the map a few times," says Sigman Heating & Air Conditioning's Sales Manager, Joel Sigman. "I'd been driving for so long I was sure I must have passed it."

The long trip was worth it, however: the homeowner had researched geothermal systems, and had asked the local WaterFurnace dealer for references. He and Joel hit it off, talked about their ideas for the system, and the papers were signed the same day.

"Joel was all ears, and very technology savvy," says the homeowner, John Bohn. "He was always ready to learn and try the next cool thing. It was very refreshing working with him." In particular, John, as founder and co-owner of AGC Engineering, wanted to use his company's plate heat exchangers for heating the pool and spa, and pre-heating the home's potable hot water.

"Our heat exchangers are usually used for sanitary applications such as pasteurizing milk and juice," explains Bohn, who has a degree in agricultural engineering from the University of Wisconsin. "But I knew we could use them in my home, and Joel was completely open-minded about that."

Bohn's beautiful European French home has 2,800 sq.ft. of living space on the main floor, and 1,525 sq.ft. on the second floor. The home sits on a corner lot, and all four sides of the home are visible from the street. One thing that's not visible, however, is an outdoor condensing unit. That's because Bohn wanted it that way.

Bohn also wanted to control his master bedroom suite separate from the rest of the main floor, a guarantee that the system would be quiet, and floor warming under all the tile and marble floors. In short, he wanted the best.

When a homeowner wants the best, he or she turns to the best: winners of Contracting Business magazine's Quality Home Comfort Awards. Sigman Heating & Air Conditioning won a Quality Home Comfort Award for a geothermal comfort system installation in 2004, so Joel and his team were wellqualified and well-prepared to deliver the comfort system this demanding homeowner desired. Joel knew that a geothermal system would help create the indoor environment that would do this exceptional home justice.

To start the job off right, the equipment was sized for the home using the Right Suite residential load calculation program. A total load was run for the house, as well as for each of the individual rooms.

The load calculations revealed that a 4-ton unit was needed for the main floor. The two-stage unit chosen by Sigman has a variable speed blower, hot water assist, and uses R-410A refrigerant.

A single supply trunk line was run for the main floor. A WaterFurnace Intellizone control board was used with an Arzel Zoning Technologies interface panel and dampers to zone control the master bedroom suite and office from the rest of the main floor.

The second floor was zoned with its own 2.5 ton split system, connected to a Bryant variable speed air handler with 10 kW auxiliary heater. The duct in the attic is insulated with 1/2-in. liner, and the joints were sealed with mastic to minimize leakage. Both systems are equipped with Bryant electronic air cleaners.

The nine tons of loop for the geothermal system were vertically drilled to a depth of 150-ft. A 11/2-in. supply and return enter the house, then are teed and reduced to 11/4-in. The piping then goes to a two-pump flow controller for the 4-ton and 2.5-ton forced air units, and to another two-pump flow center for the other water-to-water units. The flow controller is wired into one unit, then the other unit is slaved to a pump that will start up with a call from either system.

Radiant floor heat was used for the tiled floors in the foyer, kitchen, dining room, half-bath, mater bedroom, and upstairs bathroom. The radiant floor covers approximately 1,435 sq.ft. The floor is heated with two 2.5 ton geothermal water-to-water units, which are also sized to heat the pool and spa.

The radiant heat is under the subfloor. The floor joists are on 16-in centers, and there are two pipes between each floor joist. The pipes are held in place with heat transfer plates that are 20-in. long. Each plate is separated by 4-in., and Sigman installed insulation below the pipe.

There are nine circuits of radiant floor piping. They terminate into a Heatlink Twist and Seal deluxe manifold assembly.

The water-to-water units are tied into two 50-gal. storage tanks, and the water is circulated with Taco 007f pumps. The units have internal temperature sensors, and the pump is cycled every 10 minutes to sample water temperature in the storage tank. If the water temperature exceeds the differential setpoint in the unit, the compressor comes on to satisfy the setpoint.

The two water heaters are tied together, and water is circulated through a main circulation loop using a Taco 008f pump. The radiant floor uses a Taco 008f circulating pump to draw water from the main circulation loop. A sensor in the floor controls the radiant heat. The sensor is tied into a Johnson Controls A-419 electronic temperature controller. Once the desired floor temperature is set, on a call for heat the controller brings on the circulating pump.

Even though the radiant piping is not under the living room, the radiant heat is under about 65% of the main living area, and has become the home's main source of heat.

The pool and spa are heated with water-to-water geothermal units. There are two 11/4-in. polyethylene lines that run across the basement to two titanium plate exchangers. The plate exchangers are made by Bohn's AGC Engineering. The water is circulated to the plate exchangers using a Taco 0010f pump. The pool and spa are controlled by a control board installed by the homeowner.

The hot water assist option is used with the 4-ton geothermal unit that heats and cools the main floor. It's also used to supplement the potable hot water. The circulation loop runs from the cold water supply into the geothermal unit, and back into the bottom of the water heater. The desuperheater (hot water assist) creates nearly all of the hot water in the cooling mode, and some of the hot water in the heating mode. The water-to-water units are also used to heat the potable hot water. The homeowner installed a plate heat exchanger to separate the potable water from the radiant water.

Sigman also installed two Fantech bathroom fans. The master bath fan draws 150 cfm and has an outlet in the shower/bath and toilet area. There's also an outlet over the fish tank in the master bedroom. The second fan draws 400 cfm and has four venting points. It vents both halfbaths on the main floor and both bathrooms on the second floor.

"The mechanical system was designed to give the highest levels of efficiency, comfort, and quietness," says Joel Sigman. "This was accomplished with geothermal equipment, radiant floor heat, and a carefully designed zoning system. Since the water-to-water units heat the pool, spa, radiant floor, and some potable water, they are used to their maximum capabilities and can be used 12 months of the year."

One interesting element of this job is the use of an Arzel zoning system in a newly constructed home, as Arzel's forte is generally retrofit applications. Joel has a story about that.

"I had designed and laid out all the ductwork, and had totally forgotten to put in a trunk line to zone the master bedroom. This was an exceptionally important area to zone, too, as the zone was to include Mr. Bohn's office, where he spends a great deal of time."

Making the best of the situation, Joel turned to Arzel, whose systems he had used on previous jobs. "Nobody is happy when they make a mistake, but how you handle adversity can tell you more about yourself and your company than the good times do. In this case, we had a great option in Arzel, and the main thing is that the system works very well and delivers the performance we promised."

Bohn is indeed very happy with the performance of the system in his beautiful new home. "You can tell that Joel really understands the 'layers' of a system and how everything works together," he says. "And his technicians are very good. They can troubleshoot anything. I wish I had a couple of them working for me."

Contracting Business, of course, made Bohn promise-he wouldn't steal any of Sigman's technicians. Joel's going to need them around next year when he goes for a three-peat in the Quality Home Comfort Awards.

Inside Sigman Heating & Air Conditioning

Joel Sigman is sales manager of Sigman Heating & Air Conditioning, although he prefers to refer to himself as an "informant." "I provide customers with information so they can make good decisions," he says.

Sigman Heating & Air Conditioning has been in business for 17 years, serving the St. Louis area and surrounding counties. About 30% of the company's sales volume comes from new construction/geothermal. The majority of Sigman's volume comes from residential service and replacement; the company also does some commercial construction, service, and replacement, and commercial refrigeration work.

As a company with only 14 employees, it's not unusual for everyone to pitch in on certain jobs. That was the case for this year's Quality Comfort Award-winning project at the Bohn home. "It's a total team effort here," says company president John Sigman. He also offers some insights into how his company has reached its lofty perch as a two-time Quality Home Comfort Award winner. "We're active in the Air Conditioning Contractors of America (ACCA) on both a local and national level, and take advantage of the knowledge that can be gained at industry events such as HVAC Comfortech," Sigman says. "I'm a 30-year member of the Refrigeration Service Engineers Society (RSES) and most of our technicians are certified by North American Technician Excellence (NATE). The key for us has been to avail ourselves of all the training and information this industry has to share."

Belleville, IL

4,325 sq.ft.

Total comfort system investment: $50,514.87


  • 1 WaterFurnace E048 4-ton Premier E, two-stage with hot water assist, 15kW auxiliary heater, and ECM blower
  • 1 WaterFurnace ES030 2.5-ton Premier one-stage split system with ECM blower
  • 1 Bryant FV4CNF003 variable speed air handler with 10kW auxiliary heater
  • 1 Bryant AIRAAXBB20 2000 cfm electronic air cleaner
  • 1 Bryant AIRAAXBb14 1400 cfm electronic air cleaner
  • 2 Grundfos double pump flow controllers
  • 1 WaterFurnace Intellizone zone control board
  • 1 Arzel zone interface panel
  • 1 Arzel 8 X 12 ezyslide damper - bottom mount
  • 1 Arzel 8 X 16 ezyslide damper - bottom mount
  • 1 Arzel 5-in. round damper
  • 5 Arzel 6-in. round damper
  • 2 Arzel 7-in round damper
  • 3 Honeywell digital thermostats
  • 1 Fantech DLX110 - 150 cfm inline centrifugal fan
  • 1 Fantech CVS400 400 cfm multi-port exhaust fan
  • 5 Fantech DGD 4 grilles with back draft damper

Radiant heat, pool heat, spa heat, potable water

  • 2 WaterFurnace EW030 2.5-ton water-to-water units
  • 2,300 ft. of Heatlink 1/2-in. oxygen barrier tubing
  • 450 Heatlink heat transfer plates
  • 1 Heatlink hydronic manifold
  • 2 Taco 008f circulating pumps
  • 2 Taco 007f circulating pumps
  • 1 Taco 0010 circulating pump
  • 2 Bradford White 50-gal. electric water tank
  • 3 Proflow 013 titanium plate heat exchangers
  • 1 Johnson Controls electronic temperature control and sensor