i have not been able to resolve my "check flow" warning. And before I order a new Tri-sensor with a new Manifold (the new manifold because it's easier than removing and replacing the tri-sensor with the old)... i decided to buy a Tri-Sensor Simulator. Once this comes in the mail...how do i use it? will instructions come with it? any experience with this? Will it help me narrow down the proble of the "check flow"...(which works sometimes and other times not...in recirculation or in filter mode)