Using ST wall switch to control Panasonic Green WhisperVent signal wires?

Next week I’m going to install a Phillips bathroom vent in place of the Broan vent in my bathroom. The vent works 24x7 in auto mode. It detects motion and also humidity. The fan runs at 30cfm 24x7 to promote fresh air. The motor ramps up to 150cfm and down to 30cfm automatically, depending on the sensor values. The wiring is straightforward, black, white, green. I do not need these connections to connect to ST.

There is an additional pair of red wires which act as signal wires to temporarily override the fan functions. When the wires are open, or not connected together, the fan runs in automatic mode. When the wires are connected together, the fan will instantly ramp up to max speed temporarily disabling the automatic settings until the wires are again separated from each other. In other words, use a light switch with zero voltage to separate, or connect the wires together.

These two wires will carry zero volts and act only as signal wires. My question is what kind of paddle style light switch which is compatible with ST can I use? I’m not interested in “behind the switch or other in-wall” type solutions, because someday when I move, I want the switch to work with or without ST.

I have an extra KASA ST compatible light switch. Will this work? If so, how would I wire it? I’m using some of them for light switches elsewhere in the house and have extras. I also have an extra GE add-on switch. Can I use that? If so, how would I wire it? If neither of these switches will work for what I need, what should I use, and how would I wire it? I have an electrician coming to run wires in the wall, I just need to know about the switches.

Phillips fan model FV-0511VK2
KASA switch model HS200P3
GE Switch model 12728

You would need a relay with a 120/220 volt coil between a smart switch such as your Kasa switch and the fan. The smart switch would open and close the relay.

Paul, if I understand you, the 120v side of the relay would connect to the KASA and the relay side would connect to the fan?

That is correct.

Paul, can you please make a product suggestion? When I search Amazon, there are thousands available.

Something like this should work. They also sell the same switch at Amazon. This eliminates the need for a special enclosure and they are UL listed.