Hpac 728 Hpac0712design 3 Polypropelene

Polypropylene Pipe Allays Fears About Water-Based Mission-Critical Cooling

July 1, 2012
Heat-fusion process seals the deal for data center

When it comes to data-center cooling, water-based solutions can be extremely economical. However, the thought of thousands of gallons of water coursing through piping only inches from millions of dollars’ worth of sensitive mission-critical equipment raises concerns among even the most trusting information-technology managers.

Entering 2009, Lifeline Data Centers of Indianapolis, builder and operator of commercial data centers, was planning the first phase of a new facility. It planned to use water-based cooling, but was concerned about the potential for pipe leakage. Seeing a demonstration of the heat-fusing of polypropylene-random (PP-R) pipe at Aquatherm’s booth during the 2009 International Air-Conditioning, Heating, Refrigerating Exposition (AHR Expo) in Chicago put those concerns to rest.

“The Aquatherm solution presented itself as a product that would help take the risk out of having water flowing around the computers,” Alex Carroll, co-owner of Lifeline Data Centers, said.

Carroll researched Aquatherm, learning PP-R pipe has been used successfully in more than 70 countries over nearly four decades. Additionally, he learned the heat-fusion process allows pipe and fitting to become one, eliminating potential leak paths.

“We are a pretty construction-savvy company,” Carroll said of Lifeline, which maintains in-house electrical, HVAC-engineering, and maintenance staff, “and once we saw how Aquatherm works, were just about all in. It was clear and obvious what the benefits were.”

Carroll contacted Zak Schultz of J.H. Ballenger Co., the local Aquatherm representative.

“Aquatherm’s heat-fusion connection eliminates toxic materials, glues and resins, and open flames from the piping-installation equation, and its natural R-value of 1 allows for an installation to take up considerably less space,” Schultz said.

By spring 2009, Lifeline’s construction staff had been trained and factory-certified by Aquatherm.

“Our guys were quick to get moving with Aquatherm and got up to speed rapidly,” Carroll recalled.

The System
Lifeline handled all of the construction, including the custom fabrication of the data-center cooling system.

“The cooling system is pretty basic,” Carroll explained. “We use Hanbell compressors and rooftop fluid coolers, which are basically like a radiator with a fan on it.”

The system cools water carried from the rooftop to the data center by 3-in. Aquatherm Climatherm SDR-11 pipe mains. Once the water is inside of the data center, multiple dual 3-in. loops carry it to air handlers, which are connected with less than 10 ft of 1½-in. Climatherm.

Carroll said Lifeline runs water at a constant 42°F, just cold enough to require insulation. According to Steve Clark, PE, CEM, Aquatherm’s president, “Depending on the application’s minimum operating temperatures and maximum humidity levels, Climatherm can be installed without insulation and still produce no condensation during normal operation.”

Carroll said Lifeline did not have to insulate the Aquatherm couplings and fittings because of their essential double thickness and the R-1 insulation value of PP-R.

Addressing Customer Concerns
When Lifeline sells its services to customers, it sometimes gets asked how its data center is cooled.

“Customers do care about Aquatherm pipe being in the data center,” Carroll said. “They have initial concerns where they don’t want water in there, but we explain and show them the fusion process and explain the warranty and the insurance that they get through Aquatherm, and before you know it, they are all about Aquatherm.”

With some customers having 5 to 10 kw in a cabinet and others having only 2 kw, the facility’s power density varies widely. The cooling system, however, runs smoothly.

“We do have some Schedule 80 PVC (polyvinyl chloride) in the mechanical room, but it’s not around the computers,” Carroll said. “We only use Aquatherm around the computers because it’s just more durable, and the welding process per piece and per coupling creates a continuous system that’s leak-free and much more solid. The system has had zero leaks and has been 100-percent trouble-free.”

"Can't Afford Trouble"
In terms of materials, Aquatherm was more expensive than chlorinated polyvinyl chloride and about even with steel when factoring in labor. However, Carroll explained the cost is justified based on the security PP-R provides.

“Somebody’s not going to bump it and crack it—it’s trouble-free,” Carroll said. “Once you get a data center up and running, you can’t afford trouble.”

As of May 2012, Lifeline had about 30,000 linear feet of Aquatherm pipe installed in the facility. Carroll said another 10,000 sq ft will be installed in 2012, with probably another 10,000 sq ft to come in 2013. Additionally, the company plans to convert a 2.5-mw, 20,000-sq-ft facility to water-based cooling utilizing Aquatherm piping next year.

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