MultiPurpose Sensor temp not triggering action

I setup an automation between a heat lamp controlled by a SAMSUNG SmartThings WiFi Plug and a Samsung SmartThings GP-U999SJVLAAA Door & Window Multipurpose Sensor.
The automation is set to read the sensor’s temperature and turn on the heat lamp if it dips below 85deg F and turn off when it rises above 95deg F.
The sensor’s temperature is reading accurately according to the SmartThings app. I can trigger the SmartThings plug to turn on the heat lamp manually just fine.

The problem is, the rule to turn the lamp on when it reaches a low temp doesn’t trigger.
If I manually trigger the lamp, at some point the lamp turns off. I assume because the high temp automation is working. However, when it reaches the low temp, it doesn’t kick back on.

is this lizard going to fry when the lamp turns on and never turns off?

Eric, thanks for the concern. This is not in a terrarium, but open air. Yes it is pretty inefficient, but the lizard does not like enclosures of any kind and he is pretty spoiled. He has an entire bedroom to himself with a window he stares out all day long. Also, the upper limit seems to work just fine. If I turn on the heat lamp via SmartThings, it will reach the upper limit and turn off. It just never turns back on. The rule to turn it on seems fine to me, just not working.

Can you post the screenshot from the working automation?


This seems to be working correctly to turn the heater off.

Did you ever get a solution to this? I have the exact same problem, minus the lizard.

looks ok…

What does history say for that sensor, is it reporting, is it recording a new temperature value? “THEN” actions only happen on the actual report of change in temperature.

I’d test with a diff sensor.

Sorry for my delay in follow up. Unexpectedly, it just fixed itself. I didn’t spot anything in release notes for a SmartThings Hub update that addressed this issue. I didn’t changed the programming. Sensor readings all seem as they were before. I wish I had a root-cause resolution for you.

Looks like it’s working for me now by itself as well. What’s interesting is that originally I had the if sensor reaches 74* F, then turn off the heater switch. Now when I go to edit the settings, it will only allow for *C. Bizarre.

Well it’s broken again. For whatever reason, my rule is haphazardly getting run. The rule I have is, if 07:15-16:00 weekdays, Sensor le 72* F, location mode night, home, then turn on heater. I can see there are multiple events being returned by the sensor just the automation isn’t kicking it on for whatever reason. Is there any way to debug automations?

the root issue is the cloud-based control, has been not reliable. IDE has detailed logs about what it sees.

IMO if the control is important then you want a hardware thermostat like Inkbird ITC-308. I would not invest too much effort in debugging the control by cloud, since I do not expect it to become reliable.

What’s interesting is that I used a simple IFTTT and it worked just fine but really don’t want to pay $5/mo to replicate something that’s native to ST. Do you know of any SmartApps that can do something similar that can run locally instead?

no - that’s why I suggested the Inkbird. Hubitat could run local. Inkbird seems simpler, which you could override/disable by a plugin-switch.

I have consigned ST to monitoring-only for important functions. Nice when it works, but use a seperate primary control method.

What I did to make this work better was I created a virtual switch that would go on and off based on temp settings. Because I only want my heater turning on m-f, 8-5pm, I set the smartlighting app to first turn off the virtual switch before 8am (even though it might already be calling for heat at that point) which means that at the next temp check in, if it’s calling for heat, it will turn it on by automation. It’s much more reactive through the local automation and seems to keep my room within 3 degrees (mostly because the door sensor I’m using only checks in 2x an hour at best). If/when I want to spend more than $10 on a temp sensor, I might get something that updates more regularly which would lead to a less variable temperature control.