Humidifier adjustment Rule for radio thermostat

Setup, Configuration and Use Scripts & Rules
1

Hi all,
Thought I’d share a quick rule I wrote up to get my humidifier settings on my CT80 to adjust based on the outside temperature. Didn’t find anything to this effect already posted.

rule "Set Humidity"
when
  Item Temperature_F changed
then
	var int Temp  = (Temperature_F.state as DecimalType).intValue
	logInfo("thermostat", "Temp_outside = " + Temp)
	if(Temp < 40){
		var int Humid =  (Temp*0.5+25).intValue
		logInfo("thermostat", "Humidity set point " + Humid)
		sendCommand(RT_TStat_THumidity,Humid)
	}
	sendCommand(RTTStatPMAMessage, "Out:" + Temp.toString)
end

Pretty straight forward, every time the temperature binding changes the outside temperature it recalculates the indoor target humidity. I turned mine down a bit from the “recommended” humidity I found online, to keep condensation from forming on my windows when it dips below freezing, by swapping the 25 for a 20 (5% lower than recommended). It might need some other adjustments based on your particular climate.

Also tossed a line on there at the end to dump the outside temperature to the CT80s display (not sure if the ct50 and ct100 have that ability)

I’ve only had a few days below 40 since I put it in place, but the few nights we’ve dropped to cooler temperatures we’ve had an easier time breathing in our house over night, time will tell how the condensation does this winter compared to years past.

2

This looks interesting. Are you using the ZWave or HTTP module for your CT80? If you are using ZWave I’d love to know more about 1) if you can read the current humidity value from the unit. 2) how you are configuring to set the comfort humidity settings and 3) how you setup the item for the message with outside temp.

Thanks.