How Does On-Demand Recirculation Work?
Most conventional recirculation pumps run for hours during the day, even at times when nobody is using hot water. When this happens, energy is lost and your water heater must continue to fire up and reheat unused water, resulting in high gas/electricity use. On-demand recirculation systems, such as AutoHot, only operate when two conditions are met:
-
There is a demand for hot water (as detected by a sensor or switch)
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There is no hot water presently in the line (as detected by a temperature sensor)
In other words, when there is no hot water demand, such as when you’re at work, on vacation, sleeping, or just hanging around the house, the system stays off. When hot water is in the line, such as when it’s coming out of the faucet, or just recently used, the system stays off, even if it continues to sense demand. Operating in this manner usually results in pump run time of less than 15 minutes per day total, and can achieve upwards of 10,000 gallons of water savings per year at a cost of less than $2.00 in energy to operate the system. Compare this with timer/temperature based systems that sees hours of run time per day, needlessly running and turning on your water heater
AutoHot works in any plumbing system, whether you have a dedicate return line or just standard plumbing, and works with any tank, tankless, or heat pump water heater.
For Standard Plumbing Systems,
Under Sink Kit Available
For Plumbing with Dedicated Return Lines
Product selection
Determining the correct AutoHot® System for your home is simple. AutoHot® system is easily configurable to match any situation. Follow the steps below, and if you need help, don’t hesitate to contact us.
choose the right system in 3 simple steps
Determine Ideal Pump Size
Identify Install Location
Select Activation Options
Product selection
Determining the correct AutoHot® System for your home is simple. AutoHot® system is easily configurable to match any situation. Follow the steps below, and if you need help, don’t hesitate to contact us.
choose the right system in 3 simple steps
Determine Ideal Pump size
Identify Install Location
Select Activation Options
Determine ideal pump size

- 55 Series Pump – Most common size, fits on most homes that are 2200sq ft or smaller, or if you have tankless water heater and less than 150 lineal feet between the heater and the furthest fixture
- 99 Series Pump – For larger homes, or when you have a tankless system with more than 150 lineal feet of pipe between the heater and the furthest fixture.
- 150 Series Pump – Oversized pump used for special applications, contact us for suitability.
identify install location

- You do not have a dedicated return line
- Retrofitting a house without an existing circulator pump
- You are installing at the end of a “dead-leg” branch line or riser
- If you have dedicated return line
- You are not installing under a sink, but are installing by the water heater
- You have an existing circulator pump
select activation options

- Wired Decora Rocker Switch (White)
- Wired Pushbutton (Chrome)
- Wired Motion Sensor (Ceiling mount or wall recessed versions)
- Wireless Push Button (Up to 1000 ft. range)
- Wireless Motion Sensor (Up to 500 ft. range)




AutoHot® Residential On-Demand Recirculation Systems (Base Models)
Part No. | Image | Description |
---|---|---|
DR000A (Gen 2) | ![]() | Residential AutoHot demand control (Gen2), no pump |
DR055A (Gen 2) | ![]() | Residential AutoHot, 55 series pump, wired and wireless button activator |
DR055A-USK (Gen 2) | ![]() | Residential AutoHot, 55 series pump, Under Sink Kit, wired and wireless button |
DR099A (Gen 2) | ![]() | Residential AutoHot, 99 series pump, wired and wireless button activator |
DR099A-USK (Gen 2) | ![]() | Residential AutoHot, 99 series pump, Under Sink Kit, wired and wireless button |
DR150A (Gen 2) | ![]() | Residential AutoHot, 150 series pump, wired and wireless button activator |
DR150A-USK (Gen 2) | ![]() | Residential AutoHot, 150 series pump, Under Sink Kit, wired and wireless button |
Accessories (for homes, order separately)
Part No. | Image | Description |
---|---|---|
WR-16A (only needed for Gen 1 controllers) | ![]() | Wireless receiver (for 1st generation models only) |
WB-S-16A | ![]() | Wireless Button Activator: Works up to 1000 ft away in open air |
WM-S-16A | ![]() | Wireless motion sensor |
HR-S-17W | ![]() | Hardwired rocker switch activator |
HB-S-13A | ![]() | Hardwired push button activator |
MBKT-19A | ![]() | Pump wall mounting bracket, set, for 55, 99, and 150 pump |
HR-S-17LED | ![]() | Hardwired LED lighted rocker switch |
HB-S-20LED | ![]() | Hardwired LED lighted button |
Commercial / Multifamily Systems
Add Suffixes to the Base Models for Additional Options
Suffix | Description |
---|---|
-USK | Include undersink kit |
Message Us
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Call Us
(866) 495-2734
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Open Hours
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info@autohotusa.com