Pierce Pumper, Руководство по эксплуатации и техническому обслуживанию

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Pierce Pumper / 3-27
OPERATION
Charging the Intake Line (Pressurized Supply)
Supplying the Pump
Tank to Hydrant - Connect Intake Hose - WITH Gated Intake Valve (continued)
6. Charge the intake line.
Once the intake hose is properly connected to the intake fitting, open the valve at the hydrant to allow water
into the intake hose. Air will escape out the air bleed valve as it is forced from the hose by the incoming water.
7. Close the air bleed valve.
Close the air bleed valve after the air is gone from the intake line.
Tank to Hydrant - Connect Intake Hose - WITH Gated Intake Valve (continued)
Perform change to external water source properly.
Water flow can stop if change is performed incorrectly.
Loss of water flow can endanger fire attack crews, resulting in death or injury.
8. Open intake gate valve.
OPEN the intake gate valve slowly to change the flow to the external supply.
Always open the intake gate valve slowly. Air in the intake line will then enter the pump slowly. Air will be
sucked through with a steady flow of water.
If a large slug of air enters the pump, the pump can lose prime. Centrifugal pumps cannot pump air. If prime
is lost, the attack lines will lose water pressure.
9. Close the tank-to-pump valve.
Once the intake gate valve is open, the water pressure from a pressurized source keeps water from flowing
from the tank. A check valve in the tank-to-pump line keeps the pressurized supply from flowing water back
into the tank.
A draft source lacks intake pressure. Therefore water can continue to be drawn from the tank. If the tank is
run dry, the pump can lose prime.
After the gated intake valve is fully open, then slowly CLOSE the tank-to-pump valve to make sure that water
is drawn from the external supply only.
10. Close tank-fill and recirculating valves.
As long as the discharge lines are flowing water, the pump will have fresh water to keep it cool. With the tank-
to-pump valve closed and the tank-fill or recirculating valves OPEN, the tank will continue to fill until it
overflows through the fill hatch.
a. CLOSE the tank-fill or recirculating valves to avoid tank overflow.
b. OPEN both valves again when pump cooling is required because discharge lines are CLOSED.