I am attempting to switch an old heater with a pentair ch250 natural gas milivolt. The qustion I have I followed the wire from my old heater to my automatic timer box. The gas valve and temperature setting knob are tied split together leading to the timer box. I do not know where to attach the wire from the timer to the pentair heater . I am thinking it would tie into the orange wire going to the gas valve Any help would be appeciated