By Terry McIver
The many windows of this residence presented a fantastic view, and significant heating and cooling challenges.
A hot tub compounded the cooling load challenge.
Tom Spall, front, and Michael Serniak combined knowledge, skill, ingenuity, and teamwork to make this project a success.
The mechanical rooms are models of efficient use of space.
We all know the best HVAC contractors' outlook on difficult projects: the more challenging, the better.
T.E. Spall & Son, Carbondale, PA, recently tackled a project that presented a unique heating and cooling predicament, and is now a threetime Quality Home Comfort Award winner.
Company owner and founder Tom Spall, in conjunction with M.L. Serniak Plumbing & Heating, encountered a custom-made version of "windows on the world," an extravagant yet inviting home situated on the shores of Crystal Lake, with a clear view of the mountains of Northeastern Pennsylvania.
T.E. Spall & Son is a $2 million company that has provided residential and commercial service in Northeastern Pennsylvania for 20 years. Its 17-person team offers new construction, add-on replacement, demand service and service agreements, and commercial Design/ Build.
The homeowner chose Spall and Serniak based on his previous experience in working with the duo on projects related to his business.
"We had established a good working relationship," he says, "and it was easy to communicate. I was present during the planning stage, and offered what input I could to help resolve any problems. For the most part, I just let them do their thing."
BEAUTIFUL VIEW, BIG HVAC CHALLENGE
The home design was inspired by the homeowner's desire for an unimpeded view of the mountain scenery.
"I wanted to make the most of the view; I wanted to bring the outside in," he says.
Spall knew immediately, however, that the windows would present a significant heating and cooling challenge. With 26 windows taking up just the front of the home, Spall needed to account for peak solar gains, especially when the window treatments were open. A six-person hot tub would also drive the cooling load higher.
The homeowner shared Spall's concerns that the system be able to overcome the challenges presented by the windows, hot tub, and the home's southwesterly exposure.
"We needed something that would shed some load," Spall explains, "That's why we opted to go with three Trane XL19i 2-stage condensing units, in tandem with variable speed indoor air handlers with hydronic, duct-mounted coils."
For the home's heating needs, Spall and Serniak realized there would also be corresponding heat loss through the glass during winter. With the radiant floor heat, and all the glass loss, the Trane units were a good supplement to the radiant heat to achieve full comfort in winter.
"Additionally, because we needed the variable-speed units for the 19i condensers, we were forced to use external coils," says Spall.
Most of the floors are finished with tile, so there was a concern over cold feet on chilly fall and winter days. It was the builder's preference to use something other than gypcrete, so the final solution was staple-up, insulated radiant panels.
"On the radiant side, there were several challenges," says Serniak. "The customer basically wanted the most sustained control and comfort he could achieve. However, we were limited on the first floor, and the entire staple-up radiant job was done in a 32-inch crawl space. We spent a lot of time on creepers throughout the entire 2,000 sq.ft. first floor of crawl space.
Another hurdle the team had to jump was adapting an 8 ft.x 10 ft. mechanical room to accommodate the boiler, water heater, and the entire boiler piping paraphernalia needed to pipe out the 19-zone system.
The heating plant is a Weil-McLain Ultra boiler, specified because of its high efficiency and its ability to bring outside air in for combustion. This was combined with an 80-gallon, indirect water heater for maximum performance.
Spall praises Serniak for his artisan's skill with the mechanical room. "Mike did an impeccable job with fitting the piping into a small space," says Spall.
The project had an assortment of other challenges, all of which tested Spall and Serniak's ingenuity and resourcefulness.
- Duct systems were custom fabricated using high efficiency, low TEL fittings for maximum performance. All systems were sealed externally, and insulated with Owens Corning duct wrap. Upon completion, all systems were balanced and tested.
- Because of the diverse floor plan and intense changing gains throughout the day, Spall used two Honeywell TZ-4 controllers with related dampers, and programmable setback thermostats to provide two-zone comfort on two of the systems.
- Eventually, the windows on the lower level are to be covered with curtains. The owner, however, was clear that he wanted the supply air grilles to be adjusted so as not to disrupt the window treatments with air throw.
Spall chose an Anemostat diffuser with 15 degree deflection, sized precisely for the required airflows and throw for each location.
The crews didn't have much room to maneuver. "We were in a four-foot crawl space that was home to two of the units, and was becoming cramped," Spall recalls. "For this reason, it was crucial for a good duct layout to allow future servicing. It wasn't much easier in the completely finished walk-up attic, where the third system was located."
So as not to interfere with space heating, Tekmar controllers were used, with an embedded floor sensor and outdoor temperature shutdown.
RETURN PLACEMENT: BY THE BOOKS
The supply side was not the only facet of the project that tested Spall & Son's expertise. The client specified that Spall find an inconspicuous location for the cold air returns. "I also didn't want giant grates in the walls," the homeowner says. "I wanted the system tucked away as much as possible, with proper noise suppression. I didn't want to hear it."
"That was tricky," says Spall, "especially in the 28-ft. high family room and dining room, which required five tons of cooling at peak load."
Spall's solution was a chase made to resemble bookcases, traveling up to within five ft. of the ceiling, with grilles on the top, all completely hidden from view. "These worked to pull the warm air at the ceiling and circulate it in the winter and cool it in the summer," explains Spall.
"This was a wonderful and challenging project that shows with communication and teamwork, you can achieve just about anything," says Spall.
"With the diversity of the two-stage XL19i condensers and two-zone systems, I'm confident we will meet the changing sensible and latent loads of the home throughout the day."
Spall's got it right. Successful projects are supported by clear communication, dynamic vision, ingenuity, and a team attitude. That much is clear as glass.
T.E. SPALL & SON