You are operating two lines, one with 300 feet of 2 1/2 inch hose and a 1 1/8 tip, and the other with a fog nozzle of 185 gpm. What is your pump discharge pressure?

To determine the pump discharge pressure when operating with two different lines, you need to calculate the friction loss in the hose lines and then add any additional pressure required for the nozzles.

When using a 2 1/2 inch hose with a 1 1/8 inch tip, you can estimate the friction loss from the hose as well as the nozzle pressure. The friction loss for a 2 1/2 inch hose is typically around 2.5 pounds per 100 feet. For a 300-foot length of hose, you would calculate the friction loss as follows:

Friction loss = (Length/100) x (Friction loss per 100 ft)

Friction loss = (300/100) x 2.5 = 7.5 psi

Next, for the nozzle operating at a flow rate of 185 gallons per minute (GPM), you need to consider the nozzle pressure. A fog nozzle will generally have a discharge pressure of around 100 psi.

Therefore, you add the friction loss from the hose to the nozzle discharge pressure:

Total pump discharge pressure = Friction loss + Nozzle pressure

Total pump discharge pressure = 7.5 psi + 100 psi = 107.