## How do you set the pressure on a fire pump?

PRESSURE SETTINGS Set the jockey pump start pressure at approximately 10 psi less than the jockey pump shut off pressure. Set the main pump to cut in about 5 psi less than the jockey pump start pressure, and cut out at the same shut off pressure as the jockey pump.

### What is the pressure of fire pump?

Fire pumps are rated by the manufacturer to produce a certain amount of net pressure (typically between 40 and 250 psi) at their rated flow.

#### When should you switch from pressure to volume?

Volume Mode should be used when pumping more than one-half the rated capacity of a pump. It should be used during defensive operations (i.e. Master Streams) and when drafting. TRANSITIONING BETWEEN PRESSURE AND VOLUME MODES – Typically, the mode should be set at the start of pumping operations before throttling up.

How do you calculate fire pump discharge pressure?

Calculating Pump Discharge Pressure

1. Step 1 – Draw a picture of the hoselay.
2. Step 2 – Add PDP formula to drawing.
3. Step 3 – Enter nozzle pressure & GPM used by each nozzle.
4. Step 4 – Determine the GPM in each hose.
5. Step 5 – Calculate the friction loss for each hose.
6. Step 6 – Calculate the friction loss total.

When pressure on a gas goes down what happens to its volume?

As the pressure on a gas increases, the volume of the gas decreases because the gas particles are forced closer together. Conversely, as the pressure on a gas decreases, the gas volume increases because the gas particles can now move farther apart.

## When pressure increases then the volume must?

In other words, the volume “V” is inversely proportional to the pressure “P”. Thus, if the pressure “P” increases, the volume “V” will decrease.

### What is maximum discharge pressure?

The maximum suction pressure plus the maximum differential pressure that the pump is able to develop when operating with the furnished impeller at the specified speed, specific gravity, and pumping temperature.

#### What is the jockey pump pressure?

Jockey pumps are normally sized for 1% flow and a 10 to 20 PSI higher pressure of the main fire pump.

What pressure should be maintained for a fire hydrant?

The fire pump shall be horizontal end suction centrifugal type. It shall have a capacity to deliver 2280 LPM as specified, developing adequate head so as to ensure a minimum pressure of 3 kg. per sq.cm at the highest and the farthest outlet. The delivery pressure at pump outlet shall be not less than 6 kg.

What is the required pressure for fire hydrant?

Hydrant mains should be tested with the pump delivering at its maximum pressure with all the hydrants outlet closed and thereafter, with at least three adjacent hydrants opened to see that the hydrant yield the minimum output of 1 125 litres per minute at a minimum pressure of 5.25 kgf/cm2 or higher, if needed.