If you thought on-demand or "tankless" water heaters were limited to residential applications, think again. Tankless water heaters are ideal energy and space-saving devices for a variety of commercial applications, including hotels, restaurants, warehouses, health care facilities and educational buildings. Tankless water heaters also can be used in industrial applications to meet smaller, isolated water heating needs.
Replacing a traditional tank type hot water system with on-demand units can result in energy savings of 15 to 20 percent. While any tankless unit are particularly useful in small and mid-sized business environments, many manufacturers also supply systems specifically designed for larger commercial uses and specialized industrial applications.
What are Demand Water Heaters?
On-demand water heaters, common in Japan and Europe, began appearing in the United States about 25 years ago. Unlike conventional tank water heaters that must maintain the 120-140°F temperature of water in the storage tank, tankless water heaters heat water only as it is used, or on demand. The unit is small and mounted on a wall along the water line near where the hot water is needed.
A tankless unit has a heating device that is activated by the flow of water when a hot water valve is opened. Once activated, the heater delivers a constant supply of hot water. The output of the heater limits the rate of the heated water flow. Tankless water heaters are available in both gas and electric-powered models.
Benefits and Drawbacks
Tankless water heaters offer many advantages to commercial and industrial customers. They heat water only as it is needed, eliminating the need to use energy by constantly heating a tank full of hot water. The typical tankless unit is also compact and can be wall mounted for space saving. Most are available in outdoor- as well as indoor-mounting configurations.
- No standing pilot as in traditional tank systems. Saves energy by operating only when needed.
- Compact, wall mounted unit saves space.
- Available in indoor or outdoor designs.
- Life expectancy of twenty years (up to twice as long as tank units).
- Replaceable parts can extend the life of the unit.
- High initial purchase price.
- Limited flow rate does not allow for simultaneous use such as showers and laundry.
- In gas units, a higher BTU input may require a large gas supply.
- In electric models, a higher amperage may require a larger power supply.
- Replacement parts may not be readily available in certain areas.
Commercial and Industrial Uses
Demand water heater systems offer a wide variety of scenarios for commercial and industrial applications. For example, a restaurant may use hot water only at the end of the day for clean-up operations. A wall-mounted tankless unit could provide the hot water when needed while avoiding the cost of running a large tank system all day long, and also free up space for other critical operations.
Medium-sized hotels and motels will normally have long periods of low usage punctuated by periods of peak demand for hot water. Installing multiple tankless water heaters would provide a perfect energy savings opportunity. Other uses include laundry facilities in hospitals and nursing homes, showers in schools and campgrounds, restroom facilities in office buildings and college dormitories, and retail applications such as beauty/barber shops that require intermittent hot water capacity.
Demand water heaters offer solutions in many industrial applications as well. Among them:
- Heating of pure and deionized water.
- Emergency drench showers and eyewash stations.
- Providing hot water to remote locations with no hot water lines or infrastructure.
- Mobile facilities in mining, forestry, oil and gas industries, etc.
- Transportation industries (ships, railcars, aircraft)
Tankless water heaters can reduce energy use in specialized applications, avoiding the time and expense of supplying hot water lines from large boilers to distant locations. A wall-mounted unit near an eyewash station is a good example of a compact system that is able to supply warm water at a lower cost without taking up much space. Depending on the water heating requirements, tankless water heaters can be appropriate for a variety of applications to reduce energy costs.
*Information courtesy of Questline Tech Resources, Columbus, Ohio