School Goes Tankless, Saves $70k Annually

Replacing a 2,300-gal. electric water heater with a tankless system resulted in a two-month ROI and signifi cant annual energy savings.

Located in Overton County, Livingston Academy High School in Livingston, TN, is a public school with approximately 900 students. Operating the school’s 1970s electric water heater had been draining the school’s funds for a while. It was time for a change.

In 2011, the school took steps to replace the old water heater with a more efficient water-heating solution. What wasn’t known at the time was how much

Top. When the Livingston Academy school replaced its 2,300-gal. electric water heater with a tankless system, the school realized a $70,000 annual energy savings.

Above. The seven tankless units have a 1.7-million-Btu capacity and the system paid for itself in two months. more effective that new system would be at meeting the school’s hot water needs and reducing energy costs. In fact, throughout 2012, the school saved $65,000 to $70,000 in energy costs as a result of installing a Rinnai tankless water-heating system. Rinnai America Corp. is located in Peachtree City, GA.

The school’s maintenance staff began working with Jim Palmer, territory sales manager for C.C. Dickson Co., Wilson, NC, one of the largest wholesale distributors of HVAC/R equipment in the Southeast, to design a new, more energy-efficient system.

Palmer had seen the benefits of tankless water heaters in other applications, but had not yet been involved with such a project. After much consideration, Palmer and school administrators collectively decided that Rinnai Ultra Series condensing tankless water heaters would offer the school optimal energy savings and effectively meet its hot-water needs.

Removal of the older, 2,300-gal. electric water-heater tank from the school’s mechanical room proved to be a challenge. “The old tank was the size of a car. It took up half the room and we had to cut it at the bolt forces to get it out the door. The tankless units are only one-third the size and are a much more powerful system. It’s quite impressive,” said Palmer.

The project’s team worked with Rinnai engineering in the design and installation of a sophisticated rack system for the mechanical room. Collectively, the school needed seven Rinnai condensing tankless units—approximately 1.4 million Btu—to adequately supply hot water to its five mop sinks, 75 regular sinks, and 46 showers. Each unit is individually vented through the building’s roof. An existing gas line in the mechanical room allowed the team to easily make the switch from electric to gas.

Condensing units were selected because they capture latent heat before it escapes into the vent system and transfer it to the water being heated. This improves energy efficiency. Condensing units offer an energy factor rating as high as 0.95, compared with 0.82 with non-condensing tankless units.

Because the wait time for hot water could be substantial in a large school facility, one of the tankless water heaters is on a recirculation system, which moves hot water in a loop close to fixtures, so there is less of a hot-water wait.

The new tankless water heaters also feature unit redundancy, which means that if one, two, or more units require maint enance, the remaining units seamlessly continue to provide on-demand hot-water service to the school. Therefore, even if one unit shuts down, the system still operates with approximately 80% to 90% coverage.

“Redundancy was another major reason the school decided to go with a tankless system,” said Palmer. “If one unit wasn’t working or needed maintenance, the school would still have hot water. You could just work on the unit that needed to be worked on without shutting down the hot-water supply.”

The whole project took about six months, including specifying equipment, developing a plan, and completing installation during summer vacation. “Once we had everything figured out, it went very fast,” said Palmer. “Rinnai experts helped us specify the right number of units for the school’s hot-water demands. They gave us good advice and direction and what they recommended is providing fantastic results.”

“We never imagined how much money it would save,” said Palmer. “The system paid for itself in two months. The school is still amazed at how well the new system is working—that something that compact could deliver the hot water they need. They have no complaints. Not one.”

Overton County School System decisionmakers are planning to gradually switch to Rinnai condensing tankless water heaters in all schools. Additionally, when the Overton County Sheriff’s Department heard about the energy savings experienced at Livingston Academy, it contacted Palmer for information.

“We are looking for more and more opportunities to use tankless water heaters. People see the value of them and the results speak for themselves,” Palmer said.

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Want more information? The resources below are linked in our digital magazine at cbpmagazine.com/digital/apr2014.

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Evaluate the specifi cations of the Rinnai RU98 unit at http://www. Evaluate the specifi cations of the Rinnai RU98 unit at http://www. rinnai.us/commercial/tankless-products/ru98i-reu-kb3237ffud-us. rinnai.us/commercial/tankless-products/ru98i-reu-kb3237ffud-us.

Download the RU98 spec sheet at http://www.rinnai.us/ Download the RU98 spec sheet at http://www.rinnai.us/ documentation/downloads/RU98i_KB3237FFUD_spec_sheet_ documentation/downloads/RU98i_KB3237FFUD_spec_sheet_ tankless_water_heater.pdf.

Download a manual for designing tankless-water-heating systems Download a manual for designing tankless-water-heating systems at http://www.rinnai.us/documentation/downloads/R-TRWH-E-02_ at http://www.rinnai.us/documentation/downloads/R-TRWH-E-02_ Rev_D.pdf.

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Jail Windows Provide Daylight, Security

Two types of detention-grade windows add daylight, aesthetics, and security to a Chicago jail addition.

The Cook County Department of Corrections, Chicago, installed Hope’s steel detention windows in the newest addition to its campus. T he latest addition to the Chicago Cook County Jail’s sprawling 96-acre campus in the city’s southwest corridor is a $90 million, five-story, 290,000-sq.-ft. Residential Treatment Unit (RTU) and Reception Classification Diagnostic Center (RCDC). The addition serves multiple functions for the Cook County Department of Corrections. It also meets LEED Silver certification, as must all new Cook County facilities.

The RTU contains approximately 1,000 beds to provide inmates with medical care and specialized psychiatric treatment. The RCDC serves as the jail’s central intake/discharge space, designed to process 300 to 400 pretrial male and female detainees into the jail system each day, discharge a roughly equal number, and hold and transfer about 1,500 detainees from other sites using new and existing underground tunnels connected to court buildings and other related facilities.

“With all of this movement of inmates, it was critical to the Department of Corrections that all of the facility’s spaces meet the highest security standards,” said Paul Reich, project manager for Roula Associates Architects Chtd., Chicago, the firm that designed the facility

Daylight is an important component in any facility, but usually not difficult to accomplish with conventional commercial windows. Windows in a correctional facility become a much different challenge for a variety of obvious reasons. To meet the stringent requirements of this design, the architects specified SA30 series steel/aluminum fixed detention windows and the STB30 series

steel fixed thermal-break detention windows, manufactured by Hope’s Windows Inc., Jamestown, NY.

The SA30 windows incorporate an interior secure steel frame with an exterior thermally broken aluminum glazing frame. These window assemblies are designed for extreme weather climates.

The interior frames are custom formed using 12-gauge 302/304 stainless steel. They are designed with exterior and interior sub-frames that eliminate removable covers. The interior frames are fusion welded at the corners and are back welded for superior strength and water tightness. The tool-resistant steel meets or exceeds ASTM A627-03.

The exterior frame is constructed with 6063-T5 alloy aluminum, that is filled and has a de-bridged thermal break. Exterior frames are screwed, gusseted, and sealed. Hope offers unlimited glass options.

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The STB30 series windows feature a vinyl thermal-break sandwich between the interior and exterior frame. As with the SA30 windows, the interior frame is custom formed 12-gauge 302/304 -grade tool-resistant stainless steel that meets or exceeds ASTM A627-03.

The frames are designed with exterior and interior sub-frames that eliminate removable covers. The sub-frames are separated by a 1/4-in. rigid-vinyl separator for thermal enhancement. The windows meet the same impact specifications as the SA30 units.

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The windows provide daylight to this LEED Silver facility while meeting all correctional-facility standards for tool and impact resistance.

tion/security design for the facility, including the specifications for the windows. “This is a highly sophisticated facility incurring a great deal of liability serving inmates with mental health issues,” said Jeff Pronschinske, CSI, CDT, director of security engineering for Arnold & O’Sheridan. “Specifying Hope’s is easy as they have a 50-year track record in the correctional market and we know their product meets or exceeds our requirements and expectations.”

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Want more information? The resources below are linked in our digital magazine at cbpmagazine.com/digital/apr2014.

Circle 9 on the Reader Service Card.

To learn more about the facility in general, read an article To learn more about the facility in publishedin publishedin CorrectionalNews magazine.

Download specifi cation information for the SA30 windows. Download specifi cation

Download specifi cation information for the STB30 windows. Download specifi cation informa