Is there an app to start fan only of my AC unit?

I’m using Zen and can’t find a way to turn the fan on only, in some schedule. I can turn fan on manually, but not in an automated way.

Rule Machine can do this.

As Bruce has said yes rule machine will do what you want, but remember your Thermostat is hard wired to the HVAC. Yes you an interrupt those wires for fan on with a z-wave relay but it can cause a problem if it doesn’t go on with the HVAC, so I suggest against doing it.Years ago I remember some of the HVAC units didn’t have a safety that made sure the fan runs when heat or air is on , and if it either called for heat or air and the fan didn’t start either did the compressor or heat.

This thermostat has a setting to simply turn on the fan. He doesn’t need to rewire anything to do that.

I totally understand that, but I have seen people that have broken the wire for the fan on and have installed a remote switch. have been wiring HVAC for 32 years, that is why I gave him the warning. As it isn’t the correct way of doing it. That is why I said it can cause problems.