Attic fan with a Z-wave Switch?

(Chrisb) #1

Anyone know what sort of power requirements the typical attic fan uses? I’m talking about the kind of fan that’s mounted in the ceiling and sucks air through the house and out through the attic.

I’ve got a timer switch on it right now, but I’m thinking of just replacing it with a z-wave switch. But I’m unsure if these suck more power than a standard z-wave switch can handle. Don’t wanna burn out $50 in a few weeks.

(Coolcatiger) #2

Any ideas on this? I am thinking to put z-wave switch for attic fan.

Any recommendation for a switch which can handle very high temperature?

(Teflon Koss) #3

You’ll want to check the amperage on the fan. If it’s anything like mine, you’ll probably need a relay:

(Coolcatiger) #4


Thanks. I have this motor for attic fan, will it work?

(Mike Maxwell) #5

I’ve got a pretty big one on order (4700 CFM), spec sheet says 600 watts, which is 5 amps.
AC motors are an inductive load and are pretty hard on relay contacts since they draw quite a bit more current during start up. So for my setup I’m using external relays run from a aeon dual micro to run it and change speeds.
Aeon dual micro link…

I have the device completed, waiting for the rest of the bits to complete the project.

Unless the intended device is rated for inductive loads, the build in relay would likely weld itself into the “on” state after some period of time.

(SimonS) #6

Old post, but would like to update it with easiest and sleekest z-wave relay + temp sensor all in one with no batteries to worry about:

Qubino 1D relay with temperature probe available @TheSmartestHouse. The relay is good till 120F degrees BUT if you attic get hotter, mounted somewhere in a wall and extend the 3ft probe cable (splice and solder). I extender mine to 12 feet - sensor still works. Probe can handle extreme cold and hot temperatures.

Also for reference, my attic fan is only 2 amps (probably 4 at startup). That relay will handle 10 so very flexible.


Looking for a high temp sensor, preferably 120v vs battery to place in my attic to monitor temps. I live in Phoenix, AZ, 2 story home, with concrete roof tiles. The roof temp can exceed 170° F, and attic temps in excess of 140°F. The sensors I’ve been looking at either cannot accurately measure/register temps over 125°F or the sensor itself cannot be located in an environment over 104°F. My primary use is monitoring. Secondary would be to control an attic fan through a Z-Wave outlet. Any information would be useful. Thanks in advance. Eric