[rohrmann]

The main reason for the red regulator is to make sure that once the propane leaves the tank as a vapor that it stays a vapor. Propane regulators in trailers do not regulate liquid only vapor. If the regulator was not there the pressure in the hose/pipe would be the same as the tank. This could lead to the vapor condensing back into a liquid. With a reduction in the pressure from the regulator to the other side of the coach this will greatly reduce the possibility of the vapor in the crossover hose turning back into a liquid. This is all based on propane’s vapor/pressure saturation points. The lower the pressure the lower the temperature to turn it back into a liquid.