Ecobee and Smart Switch connected Whole House Fan

#1

Hi,

I will be installing a smart switch to turn on my whole house fan(replacing a timer switch) soon, but wanted to get the logic down.

I have a window sensor. When it opens and the temperature outside(window contact temp) is cooler than it is inside(ecobee temp) and the ecobee operating state is idle, I want it to kick on the whole house fan.

Right now it sends an SMS to turn it on, but this is where I would replace it with the new switch. I would eventually want to set it for a timer event to run for 2, 4, 6, or 8 hours. Either that or run until inside temp is cooler than outside +/- a few degrees.

Any suggestions on how to enhance this logic or maybe a better way to design it?

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#2

Does the current SMS message arrive at the desired time?

For your timer you could do an expression that says something like insideTemp - outsideTemp > 4

#3

It does send the SMS when it meets the condition. When you say timer and give the expression as a condition, I am not sure how that would work. I would probably shut it off at a set low inside temp, if it ever reaches it(say 72), but am not sure how to restart it if the temp creeps back up.

#4

Sorry, I said timer but was just speaking in the general sense of getting it to shut off.

As for getting it to turn back on you could change the trigger on your contact to a condition of is.