Hot water recirculator

Put a wyze plug on my Watts hot water recirculator

Set Watts to “on” (bypassing its mechanical timer)

Use the wyze plug to set the on and off schedule from phone.

I use this on a remote property: on when it’s below freezing or we are visiting the property. Saved the pipes this year.


Howdy @rwburnett My house is built on a concrete slab and the master bath is on the opposite end of the house from the water heater. The hot water recirculation pump is controlled by a wall switch in the master bath.

I’ve taken your idea one step further. By putting the recirculation pump on a Wyze smart plug and by adding a Wyze motion sensor in the master bath, I created a rule to turn on the pump when the sensor detects motion. Another rule turns off the pump after running for five minutes.


I tried this a while back (with another plug & motion sensor). The hot water was running so long the cold water line became excessively hot. So keep enter out for that.

I gave up on it. But maybe it would work if I found a way to stop it from running more than once an hour.

Hi Brian. My situation is a bit different. The house is 25 years old and fortunately the people who designed the house included a dedicated hot water return pipe.

It would be nice to have a timer on the rules. So you can run it for like 3-5 minutes each time, instead of keeping it on all the time.

Also, which hot water recirculation did you end up getting and from where? I was thinking of installing one.

Hi Aaron, Years ago I installed a Grundfos pump with an integrated timer that used the cold water pipe as the return line. A special temperature valve below the most distant sink made this possible. I gave up on this arrangement because the cold water line was hot.

I reused this pump on our current house but didn’t use the diverter value. I replaced old water lines with pex (insulated) and added a dedicated return line to circulate hot water. Note: this required two check valves to keep the flow going in the proper direction.
I could set the timer pins on the pump but I prefer to control the pump only when needed. So I added a smart switch controlled by Alexa. “Pump on” or “Pump off” 4 minutes of run time gives me hot water by the time 2 cups of water has passed. Sometimes I’ll forget to turn off the pump.

Next, I’ve played with the timer feature on the smart plug but haven’t found a solution to have the pump turn off after 5 minutes by default. Have you figured out a way to do this?

Grundfos pump: UP15-10SU7P/TLC

I have a Grundfos as well, and use a motion sensor to tell Alexa to turn the pump on, and then time it for 5 minutes then off. It works amazing. I do have check valves installed at the cold water feed line to the water heater, and I have bypassed the old-school timer and temperature switches built into the pump and wiring.

Thanks Mark for your post. Do you have more than one motion sensor controlling the pump? In my case, I use hot water in two bathrooms, a laundry area and the kitchen. My goal is to have hot water after one cup of water has flowed from any faucet.

Sounds like the wyze plug is more versatile (programmable) than the smartthings plug. I’ll give it a try.

I monitor the temperature of the cross over line in the bathroom. When it hits around 95 I end the cycle by shutting off the pump (Samsung plug) and close the valve on the cross over line. That seems to work well for me.

I ran into the same problem of the cold water getting hot. Ran a pex dedicated return to the hot water tank, the house is all copper water piping. This was before even knowing about Wyze products. It is on a schedule set at pump. Now I am going to add a Wyze plug and try t his when I get my Cameras all installed outside.

Sharing what I did with my hot water recirculator. This will work with just about any pump.

This is what I did to turn my hot water recirculator on for a designated period. I created an Amazon Alexa routine (listed below) which I called Hot Water. When I say “Alexa, Hot Water” it runs the routine.

  1. Say “Turning on the pump”
  2. Pump – power on
  3. Wait 5 minutes
  4. Say “Turning the pump off”
  5. Pump – power off

You can also schedule the routine to run at a specific time (e.g. right before you get up in the morning). I prefer to simply tell Alexa when I want hot water and our schedule is not always consistent. I think this also can be done with a google home routine by saying/adding something like “turn on the pump for five minutes” but not entirely sure as I don’t use google home as my main smarthome portal.

Also, if the recirculating pump is in a unconditioned area (garage, attic, etc), I would recommend using the outdoor plug as the specs for the temperature range are broader than the indoor plugs.

I’ve tried to create a simple timed event where google home will turn on my recirc pump and turn it off in five minutes. Google home doesn’t seem to allow a timed event on appliance type controls (non- light bulbs) for safety reasons. Any advice?