Many homes have heating and air conditioning systems that are divided into multiple zones, so why not zone the plumbing system? Zoning a heating and air conditioning system allows homeowners to separately control, for example, the upstairs and downstairs temperatures to maximize efficiency. A hot water system can be divided into multiple zones for different reasons.
Two Rinnai tankless water heaters will service the 2009 HGTV Dream Home in Sonoma, Calif. The two water heaters will reside in the attic to service two different sections of the house. Carefully spacing two units minimizes the physical distance hot water must travel to the end user. In other words, the closer the water heater is to the point of use, the faster users get hot water, says Bruce Lee, 2009 HGTV Dream Home builder.
"One's going to service this end of the house which is the master suite and the kitchen, and the other water heater will service the upper-story bedrooms and downstairs powder room," Lee says. When someone wants hot water anywhere in the house and opens a faucet, they will have hot water in a few seconds, he explains.
"Another advantage of having the Rinnai on-demand water heater is efficiency. You don't have a water heater that's sitting there keeping the water hot all the time. It creates hot water only when there's a demand for it. It saves water and is more efficient," he says.