Smart Countdown Control 32 for Watts – Grundfos -Taco Style Thermostatic System


Product Info

Leridian Dynamics, Inc. fourth generation flow meter-based, on-demand Smart Countdown Control for turning on a pump when water flow is detected and running it for a set period of time. This controller is an improvement on hot water recirculation timers.

This controller is designed for use with the Grundfos – Watts – Taco style thermostatic valve systems in homes or buildings without a dedicated recirculation line (multiple dead-end water lines).

This on-demand controller can be configured and upgraded with your smartphone over Bluetooth and supports Live Flow™, Smart Timers™, and system logging.

For tank and tankless systems.

Download Android App  Android app from Leridian Dynamics for Smart Recirculation Control

Download iPhone/iPad App  iPhone app from Leridian Dynamics for Smart Recirculation Control

View the Installation Guide

(4 customer reviews)
The Smart Recircirculation Control comes with a 90-day, no questions asked, money-back guarantee.  If after installing the Smart Recirculation Control you are dissatisfied FOR ANY REASON WHATSOEVER with the performance of the Smart Recirculation Control, simply package up the unit and return it to us with a note explaining what about the product you are dissatisfied with and we will refund your purchase price minus original shipping charges and credit card processing fees*.  This guarantee applies to our controllers, Maxx-Flow thermostatic valves and Leridian Dynamics 2006SN10 pumps.

*Due to changes in the credit card processing industry whereby the credit card company DOES NOT refund credit card processing fees to our company, all canceled or returned orders will be subject to a deduction of this fee (2.9% of the transaction + $0.30) when refunded. The companies Square, Stripe and PayPal have all started doing this. In our case it will be Square that is keeping your fee for your canceled order not us. 

  • Free shipping to US and Canada on orders over $150.00.
  • Usually ships within 2 business days.

Customer Reviews

4 reviews for Smart Countdown Control 32 for Watts – Grundfos -Taco Style Thermostatic System

  1. Larry S. (verified owner)

  2. Grant M. (verified owner)

    Works as described, turned an old existing recirc pump from timer into an on demand pump, saving mone.

  3. Bruce R. (verified owner)

    This was just what I was looking for to help me take advantage of my Watts hot water pump and bypass valves. I was not able to take advantage of the pump before because it was only able to run based on time and not demand. THe Smart Recirculation Controller senses when the hot water is used and starts the pump. This get the water hot at the sink in a few minutes and provides hot showers and dish washing without wasting water. It also saves on hot water heating costs by only running the pump when needed. 5 Stars!!

  4. Mike S. (verified owner)

    Waited a long time for this unit, works as advertised and has lots of room for water flow variations.
    Great product.
    Mike S.

Only logged in customers who have purchased this product may leave a review.


The Smart Countdown Control 32  hot water recirculation timer is a simple solution to the on-demand problem for houses that already have a Watts Instant Hot Water System, Grundfos Comfort System, Taco Hot-Link System, or any system that uses the plastic style of thermostatic crossover valve. This controller is Made in the USA.

This controller monitors your hot water line and when it senses flow it turns the pump on for a preset amount of time.  The default is 5 minutes but this can easily be configured for up to 15 minutes with the smart phone app. 

Once the system runs for its preset period of time, it will turn the pump off and not run again for a user configurable period of time called the dormant period

The default dormant period is 10 minutes, but can be configured for up to 30 minutes with the smart phone app.This hot water recirculation controller implements Smart Timers for hot water pumps that, when active, will run the system for the countdown period and then go dormant for the dormant period. This way, even during times when the timer is active, the pump will not be running constantly. 

Of course, outside of the timer periods the controller will still run the pump on demand.

The Smart Timers™ are disabled if the controller doesn’t sense a hot water draw within a 24 hour period.  So if you go on vacation and forget to manually disable them, no worries, they will turn themselves of and re-enable as soon as it senses a hot water draw. 

The Smart Timers™ are set via your Android or iPhone smart device.

It couldn’t be simpler!

This is the easiest way to upgrade a thermostatic system to an on demand hot water system.

These types of systems work well for homes that have multiple dead end runs.  You would install a thermostatic crossover valve at the end of each dead end run and a single pump at the water heater and both runs will heat up.

Download Android App  Android app from Leridian Dynamics for Smart Recirculation Control

Download iPhone/iPad App  iPhone app from Leridian Dynamics for Smart Recirculation Control

Additional information

Flowmeter Size



2006SN10, No Pump