SIGforum
Thermostatically controlled 120V coupler (not a plug)?
November 11, 2025, 02:36 PM
GeorgeairThermostatically controlled 120V coupler (not a plug)?
Have a good friend looking for such a thing, can't easily find but I told him I had a "source" that would point me to options in under an hour....

He's planning to put this in line to an electric powered pump/sprinkler system on his septic system. It runs at certain fluid levels, but he's wanting to delay that when it's well below freezing.
It's hardwired below ground, not a plug in. Lots of plugs out there with this capability.
If you're like me, first you have to get your head around septic sprinklers as an actual thing....
You only have integrity once. - imprezaguy02
November 11, 2025, 05:46 PM
selogicI've actually seen one of those sprinkler set ups . Weird .
November 11, 2025, 08:09 PM
petr www.optimumcontrols.comThe right way would be something like this. Logic controlled to still allow the pump to run so the level doesn't get too high to cause other problems.
November 12, 2025, 08:23 AM
SpinZoneI would wire in a Zigbee/z-wave/WiFi type enabled interrupt (switch) to the pump power line and add a temperature sensor to my existing automation hub. Using the temp input to the hub to cycle the pump power based on temp and the existing float switch (?) to cycle the pump based on level, it should meet his goal.
Of course I already have full mesh coverage set up on an isolated network so this would be an inexpensive, simple solution. Starting from scratch would be a lot more involved and expensive. I don’t know of a stand alone thermostatic power interrupt, but I'm sure they exist. Most of my background is with PLC controlled systems.
“We truly live in a wondrous age of stupid.” - 83v45magna
"I think it's important that people understand free speech doesn't mean free from consequences societally or politically or culturally."
-Pranjit Kalita, founder and CIO of Birkoa Capital Management
November 12, 2025, 08:29 AM
SpinZonequote:
Originally posted by petr:
www.optimumcontrols.comThe right way would be something like this. Logic controlled to still allow the pump to run so the level doesn't get too high to cause other problems.
Good point. I made the assumption that the sprinkler side would be separate and parallel to the pump out side so interrupting one wouldn’t affect the other. Some things are worth being sure about.

“We truly live in a wondrous age of stupid.” - 83v45magna
"I think it's important that people understand free speech doesn't mean free from consequences societally or politically or culturally."
-Pranjit Kalita, founder and CIO of Birkoa Capital Management
November 12, 2025, 09:39 AM
GeorgeairVerified it's on separate line, and shared that with him. Thanks!
You only have integrity once. - imprezaguy02
November 12, 2025, 05:13 PM
gjgalliganDon't sprinklers need to be blown out to keep from freezing? Seems like just a gizmo to shut the pump off is not gonna prevent freezing.
If anything you would want the pump to run any time it is below freezing to prevent the heads from freezing and breaking.
Integrity is doing the right thing, even when nobody is looking.
November 13, 2025, 07:40 AM
Georgeairquote:
Originally posted by gjgalligan:
Don't sprinklers need to be blown out to keep from freezing?
If anything you would want the pump to run any time it is below freezing .....
He's in MS, and everything from head down is underground. Freezing hasn't been and issue the last few years.
Running constantly when below freezing would probably require someone standing at the toilet with a hose in their mouth full time.

Well, their grey water gets there too so I guess you could just leave the sinks on!
You only have integrity once. - imprezaguy02
November 13, 2025, 08:02 AM
SpinZoneA quick internet search (I was bored) show many options but they all look to be designed to turn on at freezing then to turn off. Makes sense for heater controllers, but won’t help your friend.
Has he checked with any local companies that do sprinkler systems? There may be a specialized solution that would be geared to irrigation.
“We truly live in a wondrous age of stupid.” - 83v45magna
"I think it's important that people understand free speech doesn't mean free from consequences societally or politically or culturally."
-Pranjit Kalita, founder and CIO of Birkoa Capital Management