My mom has an Coleman air conditioning unit with an add-on furnace (Model #PACO36H1021A - Serial #WAJP134225) that intermittently will not come on when it is very cold. If you flip the fan switch on and off a few times, it will usually come on. We have replaced the thermastat three times and had three different technicians look at it, but they could not locate the problem. Does anyone know what this could be?
