What is Smart Recirculation Control?

Smart Hot Water Recirculating Pump Controller

This controller turns any home or business plumbing system with a dedicated circulating line, tank water heater, and hot water circulating pump into an on-demand hot water system. 

Smart Recirculation Control from Leridian Dynamics


On demand hot water recirculation control system diagram animated image

Turns any recirculation pump into an on-demand recirculation pump. 

  • Flow-based hot water pump controller.
  • Unique dual temperature sensor design.
  • Reduces pump run time to less a couple hours a day. **
  • Includes built-in pump timer capability.
  • Easily configure with your Android or iPhone smart device. 

The Smart Recirculation Control is an On-Demand smart hot water recirculating pump controller for homes with a dedicated recirculation loop (if you don’t have a dedicated recirculation loop check out our Smart Thermostatic Control).  This control works with tank and tankless water heaters. If you have a Navien combi unit check out our Smart Aquastat Control.

The Smart Recirculation Control controller is designed to sense when hot water is drawn from any plumbing fixture and to run the recirculation pump until the water in the recirculation loop is hot. 

The microprocessor-based design monitors the temperature of the water in the loop using a unique dual temperature sensor design to ensure the water in the loop stays hot while hot water is being used.

On-Demand Operation

To operate go to any faucet and turn the hot water on then off.  The Smart Recirculation Control senses this minimal draw, checks the water temperature in the loop, and if necessary, starts the pump running.  Within seconds the water loop is hot and you are able to draw hot water.

Because the Smart Recirculation Control uses the demand of hot water to know when to run the pump, it works even when your washing machine or dishwasher needs hot water.  Unlike other on-demand hot water systems, there is no need to install switches or sensors at each faucet location and run wires, maintain wireless transceivers, or replace batteries.

Smart Timers and Vacation Mode

The Smart Recirculation Control also has a set of “Smart Timers” that can be used to heat the recirculation loop on a schedule.  But because of the dual temperature sensor design, the Smart Recirculation Control only runs the pump until the loop is heated up.

The “Smart Timers” are disabled if the controller doesn’t sense a hot water draw within 24 hours.  So if you go on vacation and forget to manually disable them, no worries, they will turn themselves off and re-enable as soon as it senses a hot water draw.  The “Smart Timers” are set via your Android or iPhone smart device. The on-demand functionality is still in effect outside of the timers.

The Smart Recirculation Control is all you need to efficiently control your hot water pump.  Because of the dual temperature sensor design, it doesn’t matter what temperature is set on your water heater, it uses the difference to know when to turn the pump on and off.  Flow meter sensitivity and temperature difference settings are easily set with your Android or iPhone smart device.

The Smart Recirculation Control Helps Save Your Plumbing. 

Running a recirculation pump continuously will accelerate the erosion of the copper piping in your home causing pin-hole leaks requiring replacement of the entire hot water supply system and water damage to your home. This is no small expense.

The Smart Recirculation Control helps avoid this expense by turning your recirculation pump into an on-demand hot water system.  Running a pump “on demand” typically reduces pump run time to less than 45 minutes a day!

Start saving water ($), energy ($$), and your plumbing ($$$) by installing Smart Recirculation Control!

Smart Recirculation Control works with all 110/220 VAC makes and models of pumps up to 1/2 hp. Our Smart Recirculation Control family of products is made with a Type B plug and socket. Other plug and socket types will require an adapter appropriate for your country.

* of the US and foreign parts, it’s hard to obtain US-made semiconductors
** typical usage for a household of 4 (link to log file example)
Based on 62 reviews
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1-15 of 59 reviews
  1. Easy to install & set up.

  2. Everything worked right out of the box. Instructions were east to follow. Only issue I had was needed to use ptfe sealant for the threaded connections to not leak. Teflon tape was not enough.

  3. Works seamlessly! Saving so much money because circulating pump is not on all the time. Triggered with the app or simply turning hot water on.

  4. Great product. Resolves/unifies all the flow sensor, high/low temp sensors and pump in one package at a fair price point. Putting this package together using misc third party component of equal quality would be tedious.

  5. I’ve had it for a few weeks now, and it is working great so far. Good instructions, relatively easy to install (even for a non-plumber), very efficient, and works as advertised.

  6. This recirculation system works really well! I was worried I was going to have to program a bunch of timers but the flow sensor kicks off the hot water recirc as soon as I need it (by briefly turning on the hot water valve). I wait 20-30s for the water to circulate and, boom, I have hot water without wasting all that water. Customer support was amazing. They answered questions quickly allowing me to design a slightly custom layout to retrofit this system in our house as we were changing our hot water heater setup. I highly recommend it.

  7. Our group researched four products and SRC32 was by far superior because of the use of a flow sensor and because it operates with a mobil phone. Solved HPWH issues with thermal stratification by reducing run time from 18 hours a day to around 1 hour. Running recirc pump is equivalent to a 350 watt light bulb under the house because of thermal losses. So we are saving money too.

  8. Perfect solution that saved my marriage! Dave is the best and super helpful.

  9. Finally installed the smart recirc 32 with help from my plumber. It was worth the money hands down . No more wife asking if r old taco circulator is on . No more timer to fool with , no more coming hm having to turn pump on for hot water. Once I adjusted sensitivity my life n hot water changed for ever. This is a life changer. If u want hot water anytime , pull the trigger n treat yourself . Great product n great people , Dave s the best! Love ya man.

  10. Amazing. I wish more people knew about these. Saves money and is very convenient. Simple to install as well. One thing that would be nice is an upgrade to the app to chart pump runtime over multiple days. That is mostly for curiosity though.

  11. Love having this automated. So much better than running the recirc loop all the time or a timer that doesn’t always match our life schedule.

  12. This was the second unit I purchased for my customers. This system is so much better than other systems I’ve use in the past and my customers love them as well ! A must for large floor plan homes .

  13. Follow the installation instructions as written and you will love the results. We are projecting a major reduction in our propane expenses.

  14. Works exactly as described and expected. Had a plumber install it as my prior experience with pressure side plumbing hadn’t been painless. It didn’t seem to work for the first day or so, so I unplugged it and ran the recirculating pump cord directly into the socket for some immediately needed hot water.

    The next day I plugged the controller back into the socket and the pump cord into the controller. From that point on it has worked perfectly.

  15. The smart controller works great. The circulator only runs a total of 20 minutes per hour during each active period now. Plus we can turn it on any time during the day by just turning the hot water on for a few seconds. This should save a lot of water and electricity. Part of lowering my carbon footprint.