I am utilizing my existing Robert Shaw 9420 thermostat in conjunction with TrueIAQ to operate the TrueSteam humidifier. The TrueIaq diagram on page 12 shows that the C wire, originating from HVAC, is hijacked from the thermostat and to be wired into the C pin on TrueSteam Internal. The RS 9420 thermostat requires use of the C wire for operation as per page six of its manual. Do I wire the C wire from HVAC to both RS 9420 thermostat and Truesteam like the routing of the R wire depicted on the True IAQ diagram?
yes must be hooked to both. tstat needs it as well as the hstat (although i dont know why) are there lights on the hstat? if so more than likely thats the only reason to hook up the common nevermind just looked at the hstat all i can say is holy crap thats complicated lots ofoverkll there considering all you really need is one line in and one out to turn it on and off. add just a couple more sets of contacts and you could have it open the garage door and start your car.. have fun