App to Turn switch on and off when the thermostat turns the heat on and off?

Does anyone know of an app that will turn a smart switch on and off based on when the thermostat turns on and off? I have a room that does not circulate the air the best but if I could turn on a fan while the heat is running it would solve the whole problem. It would be nice if it had an offset too, maybe run for a couple minutes after the heat turned off.

You can do this with webCoRE.

Thanks for the tip. I think I got it working. How does this look?

Just beware…if you are using a honeywell thermostat, there is an issue right now where the thermostat doesn’t report the correct status back to SmartThings. So, if you have a Honeywell Thermostat this rule won’t work in WebCore just yet. I’ve been trying to get a piston to turn on my ceiling fans when my A/C is on. Samsung and Honeywell are both aware of the issue and are (supposedly) working on a solution.

GRR… I do have a honeywell lyric and this doesn’t always seem work. Now that I think about it, I bet all updates that are scheduled in the lyric are not working with webcore but the ones that are scheduled in smartthings are. I guess I will schedule all temp changes in smartthings! Thanks for the tip. I would have been stumped on this for a long time.

No problem. Trust me, I was until I went into “live logging” in the IDE and saw that the status was still listed as “idle”. I just about threw my ST hub out the window. Also, it will detect the change if the setpoint changes. So, if you change the system to a cooler temp and that’s why the AC is kicking on, it will report the correct status. It’s only when the thermostat is maintaining the temp that it will have an incorrect status in ST.

I thought about running the thermostat through ST instead but the interface for rescheduling is too annoying. If your schedule doesn’t change much it might be worth it. There are some smartapps out there too that play the role of “virtual” thermostat.

Any idea on how to get the refresh to work in webCoRE? I get the bellow error which looks like it needs a parameter which I can’t seem to specify.

One time when my piston didn’t kick off, in smartthing I went to the thermostat and clicked the refresh button and it triggered the piston. I am wondering if this refresh could fix it if I could schedule to refresh periodically while it is maintaining the temp.

Error while executing physical command Thermostat.refresh([]): groovy.lang.MissingMethodException: No signature of method: physicalgraph.device.HubMultiAction.add() is applicable for argument types: (java.util.HashMap) values: [[locationZipcode:, locationId:, …]] Possible solutions: add(java.lang.String), add(java.util.List), add(physicalgraph.device.HubAction), add(physicalgraph.device.HubMultiAction), any(), any(groovy.lang.Closure)

Can you post a copy of the piston you’re trying to run?

Here it is. Just a simple test:

Yeah, that’s not going to help. The problem is between the Honeywell TCC software and SmartThings. Refreshing won’t do anything. Plus, I’m pretty sure that this is not a refreshable device…its updated via polling.

ST and Honeywell have been working on the TCC software integration. It isn’t working perfectly yet but it is better. I was able to get my fans to turn on with my thermostat using the following piston in Webcore.

In this example, i have a virtual switch that I turn on/off to control whether the fans turn on automatically or not. Dimmer 2 and switch 2 are the fan controls. This successfully turned my fans off 2 minutes after the furnace did.

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I also have a Honeywell Total Connect Thermostat, and am also trying to integrate with my ceiling fan. The issue I’m trying to solve is that it seems that my furnace runs the fan based on the furnace control board, and it seems that the Thermostat is unaware.

How has your piston been working for you?

I had to switch to an Ecobee thermostat. The Honeywell was never able to get it working correctly where it would report back when it was active and when it wasn’t. Got to be quite annoying. To my knowledge, this issue has never been fixed completely. It reports correctly if you’ve just changed the temp but not if it is recovering back to a previous setpoint.

Which model did you get?

Can you describe how accurate and often the Ecobee reports the fan activity through ST?

How ever often it is polled by ST. The DTH and SmartApp suite I use allows you to set that yourself. and it’s not just the fan, it reports everything.

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I’ve been looking at this also for the purposes of turning on an outlet when the Thermostat turns on the AC. Using the Honeywell 8000/9000 Thermostat, it seems that it does report the status change successfully but there is quite a bit of lag before my piston executes. From what I can tell, it seems that there must be some polling cycle and the ST status is updated on that interval instead of in real time. I didn’t time it but it was something like 2-3 minutes at least. But, it did update and turn the outlet on and off.

I wish I could find a battery powered z-wave device that would trigger when the 24vac thermostat line is activated.

I tried to do that. I bought two 24 VAC relays and hooked them into the lines for heat-call and cool-call in my furnace. The current draw wasn’t high enough to activate the coil on the relay. So, not only did the relay not activate the detect it being switched, the heat and AC no longer worked.

The 8000/9000 might be responding better than the wifi programmable 7 day which is a 6000 series. That’s what I had. But the problem I reported was confirmed by honewell and ST developers as an issue on the cloud-to-cloud integration. Then again, they may have addressed it. But it doesn’t sound like it has been.

Well, some good news here. I think I have this basically working.

I confirmed that the delay is due to the polling cycle which is exactly 5 minutes. So, depending on when the Thermostat kicks on you might have up to 5 minutes delay before it reports that status to ST / WC. That’s not ideal and there doesn’t appear to be any easy way to change the polling frequency of the default Honeywell device so what I did was simply create a WC piston that is set up to run every 30 seconds and if the thermostat isn’t set to “off” then do a Poll. I also tried executing a generateEvent() and that also seemed to work but I ended up with Poll.

Regardless, it forced ST to actively poll Honeywell and now the window AC outlet (Zooz Power Switch actually) turns on within 30 seconds. The same worked with turning the temp up (forcing the AC off) or changing the Thermostat to another mode than cool. I went with 30 seconds because it discouraged setting an interval for more than 30 seconds but I am betting it would work if you went less…just a lot of junk traffic though.

Here’s the simple 30-second “AC Poller”:

Which then forces events (visible in ST logs) and feeds this “AC Tracker”:

Pretty crude but I am not sure offhand of a more elegant way of doing this short of using a local device to detect whether there is 24vac flowing to the AC circuit.

As far as said “relay”, there was this dry contact detector from Aeotec but for reasons unknown they no longer make it (old stock still out there though). I think that would have worked because the Thermostat is acting like a relay but what I am not sure of is if you would have to put a load in the circuit since what you would be doing is shorting the 24vac to its neutral/return but I don’t really know.

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Just an update on this. I got an Aeon Dry Contact 5th Gen Sensor for $25 off of eBay (Aeon no longer makes them, why I have no idea) and it could not have worked better. Your Thermostat acts as a dry contact circuit - meaning no voltage/current is applied normally like a wet contact where the juice is active always awaiting a switch to allow the current to flow. It’s not a short due to the way that the Thermostat creates the circuit using diodes - but that’s neither here nor there.

Basically, the Aeon sensor acts as a z-wave plus open/close sensor that by default is in the always closed state and when the 24Vac circuit is closed (A/C, heat, whatever on) then it goes to the open state and vice versa when the thermostat turns off. From another post I found I could use the Tweak DTH to reverse the state to be always open (just to make it more logical, not really required) and then did a basic Smart Lighting control to turn the Zooz Power Switch on when the Aeon sensor closed and off when it opens up. The thermostat wires (the yellow one or the Y (compressor) terminal and the blue common C wire) just plug into the two terminals of the Aeon sensor.

Response is in the 100s of ms range - even though the Zooz DTH runs in the cloud. No polling, no fooling around. Plus, I can add as many window units (with Zooz switches) as desired and move them around without concern. Frankly, you could wire all your thermostat outputs with the Aeon sensors and control anything with it. While it isn’t sold anymore (just old stock out there) I am guessing that their latest water sensor might work the same way since it accepts an external sensor which works on the normally open concept also.

I just love it when a plan comes together.

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I’d like to give this a try. Could you post a photo of your sensor connected?