Control of a 2-speed house fan?

[beelzerob]

I have a whole-house fan installed, and the switch that controls it is a little rotary switch with Off, Low, and High settings. I'd really like to be able to control this fan via automation. I have my house wired for OnQ (which means there's a cat5 wire on the top of the gang box), but I don't see a product they offer that would control this.

I suppose I could just wire it to a relay and bypass the "low" speed wire (which presumably halves the voltage), so that the relay will just toggle on the fan at High setting. Is there any chance this fan would respond well to a dimmer switch? I've heard that's in general a bad idea.... Or do I have to just contact the manufacturer to find out?

 

[CollinR]

Your relay can do exactly what you want if it's double throw, just put it ahead of the existing switch and it can send full power (high) to the load or break the circuit (off) or send power to the existing switch which you leave in the Low position. However this might not be so pretty if it's within sight.

 

[beelzerob]

Your relay can do exactly what you want if it's double throw, just put it ahead of the existing switch and it can send full power (high) to the load or break the circuit (off) or send power to the existing switch which you leave in the Low position. However this might not be so pretty if it's within sight.

thankfully, at least that I thought of ahead of time...the switch is behind the door of the pantry. So, until we automate it, it's still easily accessible, but definitely concealed.

I don't think ALC/OnQ makes a double throw switch. What other control options are there for a double throw switch?