[Request] Keep HVAC fan running after thermostat goes idle

While looking at the Ecobee 3 I noticed a nice feature that keeps the fan for the HVAC running for a certain amount of time after the cooling cycle or heating cycle is done and the coils are still cold or warm.

My thermostat CT30 only has automatic and always on fan settings. Automatic turns off as soon as the AC or heater goes idle so I don’t like an app that will put it into Always On mode for maybe 20 minutes to get the rest of that “free” cooling or heating by simply blowing the fan. Then it would cycle the fan to automatic mode which would, in effect, turn it off because the AC or Heat would not be actively running.

Does this exist or would someone be interested in making an app like this?

that run-on feature is frequently built-in feature of the furnace/ac-unit controller at the air handler. 20 minutes run-on is far too long - the residual cooling or heating is depleted within 1-3 minutes. Sometimes you have to place a jumper or cut a jumper to implement the function, but it may already be done.

Also running the fan after cooling will tend to re-humidify.

Theoretically, you could do this easily with Webcore. However, my CT30 refuses to report when the HVAC starts or stops, making it pretty much impossible.

I don’t have webcore so I’ll have to look into it. What device type are you using? I switched back to the generic zwave thermostat device type and it works better than anything else I’ve tried. They must have updated it at some point.

Thanks I’ll check this out. It’s definitely not already done though, I can clearly hear the unit kick on or off and the fan stops immediately.

I’m currently using the RBoy DHT.

Give the standard Zwave Thermostat device type a try if you’re not losing any features. Its much better than it was a while ago.