To add to Steve's comments, the Aladdin modules only provide data to the dash screen for your perusal. They don't really provide control to a device, although you can adjust some Aladdin sensors themselves for accuracy, like calibrating the compass or tanks.
And the HydroHot unit is likely on your coach in the same bay as the water tank, helping to keep it from freezing with just its radiant/ambient heat.
-Joel