Comparing temperatures on different devices/error checking

Is there a way now to compare temperatures between two different devices? Since I can no longer average temps between multiple devices in a virtual thermostat, if my one device malfunctions(which it has a couple of times now that it’s an edge device), it can get quite warm in the room.
I’d like to at a minimum compare the temps between that and a different device, and if it’s greater than a certain threshold, notify me.
Alternately, is there something that can notify me if a device hasn’t changed temperature in a certain period of time?

I believe you can use the SharpTools premium tier to do math like averaging temperatures.

I’ve checked out sharptools, and it has a lot of features that I like.


I can open smartthings, and see two temperature sensors displayed next to each other on a page. I can see on is 80F and one is 75F, do the math and know there’s a 5F difference.

I don’t want to pay for sharptools just to do something smartthings should already be able to do, as all the data is right there. Something I could do a few months ago.

Hot off the press this might work for you.

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How were you averaging the values before?

Thanks, that sure is hot off the presses! I am using that driver now, so I’ll have to spend some time seeing if that will work for me.

I was using custom groovy programming, and it was working very well for me.

I find the new platform is less than optimal for what I was doing with the virtual thermostats, although it sounds as if the newer drivers being written are starting to get closer to where I was. They’re working OK now, but I’m now creating routines just to alert me to various failures.

Thanks, Rick

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This is a need that I also have, but for a different reason. In the summer, I want to run my garage exhaust fan when the intake air is cooler than the garage air. I almost bought two temp sensors and a ST hub, but was very surprised to find that this is not a standard function. I need to do this through a std function, and not use add-ons or learn to code. Is there a way to make a development request?
This community is great - first time here.

There’s no way in smart things basic to compare two temperature sensors. You could create a routine to compare one to a set number, and the other to a set number, but there’s no way to compare an inlet temp sensor with an outlet temp sensor, for example.
There’s some great drivers created by people smarter than me to use a sensor as a thermostat, but no compare to other sensors

There’s some third party add ons (Edit: Sharptools, in a previous post in this thread) that can do some pretty cool stuff, but they’re subscription services.

There may be some other non smartthings sensor systems such as wyze or tplink that you can write rules for, but I’m not familiar with who has what sensors available.

Thank you. I may check out some of those options.