Water System Design, Construction, and Operation

With an understanding of the range of water system-related issues in a hospitality project, there are several things to keep in mind when engaged in them. During design, information is needed on the water supply, its hardness, and any contaminant concerns. Similarly, the proper information on water demand in the facility is needed to correctly calculate the needs and size the water system equipment. This step is important because systems tend to be oversized, making them more costly and less efficient. This usually means engaging a consulting mechanical engineer well versed in these issues, but it can also mean partnering with a manufacturers technical team to understand the capabilities and limitations of available systems. Together, the focus should be on designing the right system for a facility, not just looking at individual pieces of equipment or components.

Taking a holistic approach to the design, construction, and operation of a complete water system solution for a hospitality facility reaps the best benefits for all involved.

Once the water system is installed, the owners and managers of hospitality buildings are appropriately concerned about smooth operations. Therefore, specifying a system where the suppliers are able to provide full and quick response to any issues that may come up can be seen as critical. Similarly, the ease of the system to be repaired and maintained with readily available personnel and replacement parts helps assure that system down time is avoided or minimized. A full warranty on all materials, equipment, and even labor will help assure an owner or maintenance staff that they have some assurance of smooth operations. In some cases, off site monitoring of the water system may be possible which, when tied with routine preventative maintenance, can help assure proper, safe, and efficient water operations for the life of the building.

Taking this holistic approach toward the design, construction, and operation of the water system produces multiple benefits for the facility owner and staff. First, optimal performance can be sought that assures the proper amount and temperature of water is provided when and where it is needed without wasting energy or water. Second, it achieves greater reliability so downtime can be minimized so guests aren’t inconvenienced or critical systems can’t function. These benefits lead to capital preservation for the owners through savings on operating expenses and full availability of income-generating guest rooms and other facilities. It can also help considerably with the management of the reputation of the property—problems with something as basic as water, safety, and comfort can drive guests away rather than appeal to them.

Conclusion

Hospitality facilities need well-designed, properly installed, and reliable plumbing systems to meet their needs for hot and cold water supply and drainage. There are clearly many choices available to create such systems that are high performing, safe, and efficient. Design professionals who can work together with specialists in this area can optimize the water solutions for specific hospitality facilities of all types and sizes.

CASE STUDY: WATER HEATING

Project: JW Marriott Hotel
Location: Austin, Texas

Scope: This JW Marriott features 1,012 guest rooms and 16 floors, 120,000 square feet of meeting and event space, two restaurants, a roof top pool. The facility is Austin’s largest hotel and event center and is within walking distance of the state capitol.

Challenge: With 10 gallons storage capacity and 4 gpm recovery per room, over 10,000 U.S. gallons of heated potable water storage, disbursed across five ASME pressure vessels, must be supplied and recirculated over 1,000 rooms. Since the mechanical rooms are located 40 feet below grade, the water also needs to circulate across 250 feet in elevation while maintaining suitable pressure and temperature. Further, the water-heating equipment is required to operate for decades without failure from corrosion.

Solution: Five large storage water heaters, ranging from 1,500 gallons to 2,500 gallons each, were built and installed on time to meet a critical installation period. Each water heater was lifted via crane, raised to the top of the building, and lowered down the common elevator shaft into the subgrade mechanical room.

Results: With a 25-year vessel warranty, Marriott is assured to have a robust domestic water-heating system to last for several decades, without fear of corrosion.

CASE STUDY: DIGITAL MIXING

Project: Marriott Kansas City Airport
Location: Kansas City, Missouri

Scope: The Marriott KC Airport features 384 rooms, an on-site fitness center, an indoor pool, two restaurants, and almost 30,000 square feet of venue space.

Challenge: Most hotel managers have learned the highest demand for hot water comes between 5 and 6 a.m. and again between 10 p.m. and midnight. It was common for hotel managers to get several calls a week from guest rooms without hot water. All they could tell them was “hot water is on the way.”

Solution: The Marriott installed a complete digital mixing station system. Digital mixing allows facility engineers to select and maintain a desired hot water temperature and to control and monitor the entire water distribution system. Its ability to react to changes in system pressure and temperature within seconds ensures safe, consistent water delivery on demand.

Results: Four months in with the new digital mixing system, the Marriott’s director of engineering says guests are happy. “And when guests are happy, building owners are happy,” he concludes.

CASE STUDY: WATER DRAINAGE

Project: Hyatt Regency
Location: Istanbul, Turkey

Scope: The Hyatt Regency Hotel in Istanbul is a five-star hotel with 284 luxury guest rooms, including 30 suites with panoramic views of the Marmara Sea. The hotel offers restaurants, a spa area, a fitness center, and swimming pools as well as meeting and event facilities.

Challenge: The facility desired the superior performance and hygiene characteristics of stainless steel piping and accessories in their commercial kitchen drainage system. However, the challenge was framed as how to displace the lower upfront cost of a conventional cast iron drainage system with a stainless steel system.

Solution: The management team at the engineering firm APEAS analyzed the differences between the two drainage systems in their entirety, not just the piping. Their results revealed the easy installation, the reduced need for pipe hangers, and especially the long product lifetime as important considerations, both in terms of time and cost perspectives.

Results: The stainless system was successfully installed. According to the team involved in the project, “Installation was easier than cast iron and the installer enjoyed assembling the system. We had no difficulties during the installation.”

CASE STUDY: WATER HEATING

  

Project: Convention Center Hotel
Location: San Diego

Scope: When the north tower of this major convention center hotel was built in 1984, its 681 rooms and 25 floors got their hot water from two 3,000 MBH copper fin water heaters and a 7,000-gallon tank.

Challenge: After 15 years, the tank was severely leaking and was replaced with two gas-fired 2,800 MBH 1,500-gallon storage tank heaters. Within only a few years, the tanks’ heat exchangers failed, and the hotel was forced to rely on its old copper fins. By 2012, both tanks were leaking and were supplied by 30-year-old, 80-percent efficient heaters. The tower would soon be out of hot water—the hotel needed to get a new system in place with no interruption in service.

Solution: The hotel tasked an engineering firm to design its new system, and it recommended six 1,060 MBH fire-tube water heaters. The on-demand, tank-less, and 96-percent efficient heaters were the answer the hotel had long looked for. Small enough to fit through a standard doorway, the heaters easily rode the elevator up to the 26th floor mechanical room. They were easily sidewall vented with readily available PVC, drastically reducing installation costs. Once installed, the onboard water heater management system ensured continual, peak efficiency around the clock. Each unit offers 24:1 turndown so it can run as low as 45 MBH input, helping the units avoid cycling and keeping the system at highest efficiency. The units’ all-stainless-steel heat exchanger design ensures maximum longevity. A remote monitoring service monitors individual unit health, logs all critical operating parameters, and helps prevent problems from developing.

Results: The hotel now enjoys 96 percent energy efficiency, compared to 80 percent previously. The hotel recently hosted a large convention that put the facility at peak occupancy. The monitoring system showed that no more than three of the six installed water heating units were required to handle the sustained peak load during the entire four days of the convention, which drastically reduced fuel bills and delivered a bigger ROI.

Peter J. Arsenault, FAIA, NCARB, LEED AP, is a nationally known architect, sustainability consultant, technical writer, and continuing education presenter. www.pjaarch.com, www.linkedin.com/in/pjaarch

Watts is a global leader in the design and manufacture of innovative water solutions for residential, commercial, and institutional environments. Products include an extensive line of flow control, filtration, and treatment products for water quality and residential plumbing and heating. Founded in 1874, Watts is headquartered in North Andover, Massachusetts. www.watts.com