Good day everyone… I was reading in the list of things Tempest data can control, or automate, and came across “can control your attic fan based out outdoor temperature” however am unable to find any more information on what’s needed. Any help would be appreciated.
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There are a lot of ways to go about this, it’s a very broad question. Probably the most straightforward would be to use Tempest with IFTTT to trigger a smart device to turn on/off the fan. There are a lot of devices and controllers that can do that.
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Rather than using outside temperature to decide if your home/office/attic is hot, I’d think you’d want to have a temperature sensor in your attic and measure the temperature in the place you’re trying to cool.
HomeAssistant and node-red are the other usual ways to do home automation based on getting data somehow/somewhere and controlling things someway/somehow. You might look around in those forums for those products or in their reddit groups.
Or you can go old school and use some kind of temperature sensor that makes power to the fan go on/off. Ages ago I used to control my PC fan with a thermistor to do kinda the same thing. The home automation forums on reddit will definitely have multiple suggestions for what might make sense for you.
Heck you could probably do it with a Philips Hue compatible switch and their automation as another possibility.
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Fans, especially a large attic fans, have inductive motors and shouldn’t be used with a typical smart switch. Not sure if Hue makes one or not, but you’ll need to find a switch that is designed for use with an inductive motor.
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why would a motor care if there is power applied or not, assuming you don’t have it thrashing back and forth wildly of course ?
AC motors are a black art/science. Many switches are not rated for an inductive load, which also means that they can’t be used with old-school florescent lights using magnetic ballasts…
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One could control a relay with the smart switch and let the relay switch the inductive load.
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My attic fan has 2 settings via thermostat. Off and on. I’m really interested in outdoor temp data controlling the attic fan as I’d like it to run BEFORE it’s too hot in the attic for the fan to try and keep up. If the Tempest temperature could somehow do the controlling I’d be happy.
An inductive motor works with a spinning magnet in a coil of wires. When you shut the fan off, the motor and magnet continues to spin which continues to generate an electric charge which back feeds voltage into the switch. If the switch is not designed to handle the voltage feeding back into the switch, it can damage the electronics of the switch.
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Yup. Not questioning your explanation, just mentioning that a temperature-controlled attic fan is a very solved problem for decades and there are lots of ways to make that happen without a weather station. Heck, some friends had one in their house 50 (FIFTY) years or more ago.
Oh yes - don’t insulate over the vents that draw house air up if the fan works by drawing inside air up into the attic. They forgot that part and had a simply unimaginable electric bill for the first month until they realized what they’d done 