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PRIME AND DISCHARGE
Performing relayed water supply (When using water from fire hydrant)
1. Determine the pump pressure in consideration of the water discharge pressure
(nozzle pressure), hose pressure loss, and height loss.
2. Foreign materials such as dirt, gravel, iron rust, etc. may go into a fire hydrant.
Before connecting a hose, open a fire hydrant to discharge water in order to
remove foreign materials.
3. When using water from a fire hydrant, use a mediation metal to connect a
delivery hose to the suction port without using the suction hose in principle.
4. Set the discharge valve handle of the pump to the full open position.
5. Gradually open the fire hydrant on-off valve. However, check the water pressure
from fire hydrant with suction pressure gauge on the pump and adjust the opening
of fire hydrant on-off valve, if necessary.
If the water pressure from fire hydrant is higher than 0.6MPa
(87psi), do not open the fire hydrant on-off valve more.
* If the water pressure from fire hydrant is higher than the
required discharge pressure, it is not necessary to start the
pump.
If the water pressure from fire hydrant has not reach the
required pressure, then start the engine.
6. If the water pressure from fire hydrant is insufficient, start the engine and adjust the
pressure to the required level by operating the throttle dial.
Stop increasing discharge pressure if the suction pressure gauge shows 0.1MPa
(15psi) or below. If it does, stop increasing the pressure and keep the throttle dial as
it is.
7. To end discharge water, turn the throttle dial to the low pressure position firstly, then
stop the engine, and close the fire hydrant on-off valve.
8
Pump pressure = needed pr height loss + friction loss
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