Searching for the right piping solution
Searching for the right solution
The recent growth of Southern Adventist University, a co-educational Seventh-day Adventist institution in Collegedale, Tenn., meant various school facilities were in need of renovation and a new structure had to be built. The renovations began in 2011 and specifically focus on various retrofitting piping projects across campus.
When the administration began to focus on the modernizations, Dave Allemand, the university’s associate director of plant services — building systems management, knew he would need to specify piping that could work for many types of projects. He tasked his lead plumber, Tim Mitchell, with researching piping options.
“We were looking for alternative piping systems because the old galvanized piping was failing,” he explains. “Our copper lines were corroding due to the chlorine in the air from the enclosed pools.”
Mitchell was introduced to Aquatherm polypropylene-random piping systems by David Ladd, an outside salesman with Ferguson Enterprises in Chattanooga, Tenn. Ladd and Mike Nix, president and owner of manufacturers rep firm Mike Nix and Associates in Peachtree City, Ga., provided Mitchell with extensive information about PP-R piping systems and the solutions they provide.
PP-R piping is a thermoplastic material made up of chains of carbon and hydrogen, explains Barry Campbell, vice president of marketing at Aquatherm. It is both simple and stable chemically, so it doesn’t contain harmful chemicals or react with its surroundings. The “R” refers to the random blend of long and short hydrocarbon chains, which provides both rigidity and flexibility, allowing the material to bend enough to absorb impact. And it is hydrophobic — it is incapable of dissolving in water.
Through his research, Mitchell learned the piping won’t corrode, scale, wear out or clog — even when hard water is involved. It was rigid enough to hang from bar joist and looked professional where visible. “PEX piping did not come large enough, and copper needed to be insulated for corrosion, heat loss and condensation on cold water lines,” he says.
One system to fix them all
When making the decision as to what piping system to use, Allemand and Mitchell had to consider the many campus buildings that needed renovation.
- Talge Hall, originally built in 1961 as a women’s dormitory and now a men’s residence hall with 383 rooms, needed a new domestic hot-water piping system as well as bathroom renovations on three floors. Mitchell and outside contractor Chris Jackson, supervisor and plumber with Webb Plumbing, Heating and Electrical Corp. in Athens, Tenn., installed a 1.4 MMBtu Lochinvar Copper Fin II boiler and used 130 ft. of 2 1/2-in. Aquatherm SDR 7.4 Green Pipe to connect three 200-gal. storage tanks.
The boiler circulates 135° F water to the first tank; the water then is routed to the other two tanks, diluted to 125° and sent to various distribution points. About 120 ft. of 2 1/2-in., 180 ft. of 2-in., 260 ft. of 1-in., 200 ft. of 3/4-in. and 100 ft. of 1/2-in. Green Pipe was used for the bathroom improvements.
“The project involves roughing in water lines in 2-by-4 and 2-by-6 walls,” Jackson notes. “This application of piping works wonderfully when insulation in the walls is complete. Also, no maintenance is involved when it is properly installed.”
The scope of work involved tearing out old copper water lines and replacing them with the new pipe. “Several lines had to be rerouted because of issues with electrical and sewer lines,” Jackson says.
Also working on the project are Dewayne Moore, Jerry Jaynes, Jeff Moses and Cody Miller — all Webb Plumbing employees. Jackson advises contractors who would do a similar project to be aware of the time involved with installation. “In the end, the result is worth it,” he says.
- Thatcher Hall, originally constructed in 1968 and currently a women’s residence hall with 257 rooms, also required a new domestic hot-water piping system. Mitchell and outside contractor David Smith, owner of Oolltewah, Tenn.-based David Smith Plumbing, constructed a similar setup and again installed a 1.4 MMBtu Lochinvar Copper Fin II boiler using about 156 ft. of 2 1/2-in. Green Pipe with multilayer faser (the fiberglass extruded layer in the center) to service three 200-gal. storage tanks.
- Ledford Hall, which holds hands-on classes in its 10-bay auto-repair shop and drafting, graphics, welding, woodworking and lighting labs, needed new piping for an updated hydronic heating application. Mitchell created a hot loop for radiator-type heaters, running 150° to 168° water through 600 ft. of 2-in. Green Pipe with MF at 50 psi.
PP-R piping has natural insulation properties and the MF piping has a low thermal conductivity. “I wanted to use it as much as possible because I didn’t have to go through and insulate any of the piping,” Mitchell says. “I can put my hand on it now and not be burned, even when 160° water is running through it.”
- The Hulsey Wellness Center opened its doors in 2008 as the university’s fitness facility. Even though the building is relatively new, two projects were necessary. A large galvanized steel piping line running underneath the center had already ruptured a couple of times due to corrosion, and Mitchell wanted to replace it with another product rather than continue to commit to future costly repairs.
Instead of digging up the concrete floor — another pricey solution — Mitchell hung 300 ft. of 3-in. Green Pipe with MF from the ceiling in Walraven hangers for a domestic cold water line, 100 ft. of which was suspended over an Olympic-sized swimming pool.
“This project was one of the reasons I chose Aquatherm in the first place,” Mitchell says. “I didn’t have to worry about the chlorine in the air eating the pipe, and I didn’t want to run steel pipe because it is heavy. When I compared the weight of PP-R to steel pipe, it came out to 6 lb./ft. vs. 28 lb./ft. PP-R also is easy to move and you don’t have to worry about people getting hurt.”
The piping supplies the center’s locker rooms and bathrooms, which also were renovated. Mitchell used 250 ft. of 2 1/2-in., 250 ft. of 1-in., 100 ft. of 3/4-in. and 150 ft. of 1/2-in. Green Pipe with MF for the updates.
The McKee Library/Museum, which originally opened in 1970, needed a new chiller and associated piping for an HVAC application. This project was especially unique, Mitchell says. The outside contractor was unfamiliar with PP-R piping and preferred to use steel pipe when he installed the chiller on the outside of the building; it took him three months to complete the project.
However, when it was time to install piping on the inside of the building, Allemand stepped in. First, he was concerned about the length of time the library would have to be shut down to weld the entire steel-piping system. Second, the library hosts an assortment of valuable materials and artifacts related to former President Abraham Lincoln and the Civil War, called the Thomas Memorial Collection. Allemand was worried about the risk of a fire starting when welding steel pipe so close to irreplaceable objects.
“We would have had to shut down the library, vacate it and get burn permits,” Allemand says.
Instead, Mitchell and journeyman pipefitter Dustin Thornbrough of Industrial Air and Mechanical Contractors, with offices in East Ridge, Tenn., and Dalton, Ga., ran 143 ft. of 3-in., 78 ft. of 1 1/4-in. and 52 ft. of 3/4-in. Blue Pipe from the steel boiler and chiller loops in the basement up to the four HVAC units on each of the three floors.
Because Aquatherm PP-R piping is joined using a quick heat-fusion welding process, both of Allemand’s problems were solved: No open flames were necessary and the library’s downtime was minimized.
“We were able to install the PP-R in two weeks,” Allemand says. “It would have taken an additional three weeks if we had used steel.”
“It takes me five minutes to do two 3-in. connections at a 90° joint with PP-R piping,” Mitchell notes. “It would have taken me an hour and a half to weld with steel.”
Aquatherm uses heat fusion to form connections. It bonds both sides of a joint into a single, homogenous material without the use of chemicals or mechanical connections, which eliminates systematic weaknesses and fail-points in the pipe, helping to ease leakage concerns.
Although Nix originally trained Mitchell and a few other university staff members on the heat-fusion welding process, several outside contractors and their employees have been educated as needed during various projects. A number of welding tools have been used as well, including Widos and McElroy fusion machines and, notably, the McElroy Spider 125 with universal clamping.
Building for the future
After seeing the many successes the university has had with PP-R piping systems over the years, Allemand requested the piping to be specified in a new two-floor, 80,000-sq.-ft. Student Life Center. The center will feature the college’s main dining facilities, a small theater, study rooms and many areas for student associations and other activities.
“We believe PP-R is, in the long run, the best way to go,” Allemand says. “We like it because of its ease of application and lighter weight; also, for most of our projects, we don’t have to insulate it. For our applications, it’s been easier to work with.”
The polypropylene piping market is growing rapidly, with a handful of manufacturers now marketing systems for mechanical applications, Campbell notes.
“To my knowledge, Aquatherm is the only company with code approvals for using PP on domestic water systems,” he says. “As increasing numbers of engineers, facility managers, building owners and contractors are discovering the benefits of working with a thermoplastic piping system that acts more like metal, the PP segment is really expanding.”
Mitchell thought all outside contractors did quality work. “They did a good job and were willing to correct anything we had issues with,” he says. “With any problems that arose, they speedily resolved and communicated any possible issues which could slow the renovations down.”
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