The whole length of the Reactor's hose is heated as a single unit based upon the temperature measured at a single point in the hose--specifically at the tip of the FTS. Graco recommends that the FTS be placed close to the gun, ideally just before the whip hose but no more than 60 feet back from the gun in order to allow the Reactor hose heat to operate in a predictable manner.
It is understood that a balance must be struck between measuring temperature at the gun and controlling temperature based on the environment in which the majority of the hose is located (interior/exterior location, sun/shade, snow, wind, air temperature, etc.). On the other hand, the closer the measurement is made to the gun, the better the Reactor system knows and can respond to changes in actual gun spray temperature.
Recirculate heated chemical back to drum in cold conditions before startup.