I have a bunch of twido plc's sitting around and I would like to put them to some good use. Im new to ladder logic but I'm learning fast, I would like to place the plc's in some of my boiler rooms to control building loop pumps , boilers and a few cooling tower fans. I already have a small program written to control the boiler on/off , loop pumps and cooling tower fans on/off. My problem is when cooler weather comes around my boiler will want to come on to keep my building loop at a set temperature and then my cooling tower fans will want to come on to lower that set temperature. Is there a way to make a summer and winter schedule with like a 6 degree difference so that my boiler and cooling tower fans don't fight each other?