I did end up downloading the vi from the other post.
Set your upper to 50 and your lower to 30 and watch what happens over time. Probe the number that you are adding and subtracting from the temp. See anything strange?
Think of the heating logic as a case structure. If the heater is off is the temp below the min? If yes turn on. The heater is on and is the temp above the max? If yes turn off. Break it down into simple steps. Create a new vi with a slider that represents temperature and create the logic to turn the heater on and off. That way you can test how the logic reacts to the temperature and not worry about the rest of the program. You might be trying to do too many things at once right now.
Is it a requirement to use the demo temp vi? I am still really confused with it. You read it in and do your average on it, but when you add or subtract for heating on/off you put the number into a shift register that goes nowhere. And then use the demo temp again that does not contain the number you just modified for the heating on/off, so it just wanders around.
You need a better way to simulate the temperature you are tying to control. But that is just me.
