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demand water heatersOn Demand Water Heater

There is a lot of interest in demand water heaters these days and it's about time. The rest of the world has been using demand or "flash" water heaters for a long time. It used to be that energy prices in the US were cheap and space was not an issue. Tank type water heaters, keeping about 50 gallons of water hot all the time, were the standard. "Tankless", or demand, water heaters are gaining popularity now because they really do reduce energy costs by heating water only as needed. Even the federal government is encouraging the purchase of these cost-saving products by offering a 10% federal tax credit, up to $300, during 2012.

We are certified installers for Rinnai tankless water heaters.

For more information and answers to some frequent questions, check out our Demand Water Heater FAQ.

Demand Circulating Hot Water Pumps

Are you wasting good, treated, pumped from a well, while you wait for your shower to get hot? Do you have to run water in the kitchen to get hot water to the dishwasher? Are you committed to water conservation? Did you know that every home wastes thousands of gallons of water a year waiting for it to get hot?

Demand hot water circulation systems are not new. They have been around a long time, but recently with our current, and predictably constant water shortage, they could be a great contributor to water conservation. The concept is, that at the push of a button, water is pumped from the hot water line back into the cold water line at the water fixture furthest from the water heater, usually a bathroom. A temperature sensor detects an increase in the water temperature as hot water arrives and shuts the pump off while you are getting ready for your shower. No water is wasted. The pump runs for less than a minute. Hot water is immediately available wherever the pump is installed, usually at the bathroom sink. Whether or not hot water is then available at other locations in your house depends on the plumbing layout. Ideally if there is only one main hot water line with small branches to the kitchen, bathrooms, and laundry, installing the pump at the end of the line should provide hot water within seconds anywhere in the house.(Remote buttons can be placed at other locations.) If the farthest point is at the end of one branch, say to the master bath, and the kitchen is at the end of another branch, this will affect the time it takes for hot water to reach the kitchen. A second pump would be required.

For tankless water heaters, the pump must have a high enough flow rate to activate the water heater. I would recommend at least 10 gallons/minute. For pipe runs of over 100’, you would need a bigger pump, over 20 gallons/minute.

These Demand systems are simple to install- you can get kits that provide the hardware you need. However, they do require an electrical outlet. In the case of a bathroom sink, on outlet can usually be added by extending wiring from an existing outlet by the sink. This is the only part of the installation that requires trade skills and incidentally, a permit. The “button” is actually a doorbell button and is low voltage. An optional remote receiver hooks right up to the unit so it can be turned on from anywhere in the house with a remote transmitter button. Read more at

There are a couple of other choices besides the ACT Kontrol system (D’Mand).

The Chili Pepper - this pump system is roughly the same as the ACT/Metlund/D’Mand, but much cheaper (<$200), and only puts out 4 gallons/minute. Many complain about noise and longevity.

Watts and Grundfos, both make pumps that mount on your water heater and have timers so you can have hot water circulating during certain times of the day. They have special crossover plumbing that mounts under the sink at the furthest point and closes when hot water arrives. They are <$300 and are simple to install if you have an electrical outlet near the water heater.

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