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If pump is equipped with a heat exchanger, drain heat exchanger using gravity and vacuum drain
on all trucks as follows: Close all open lines and drain cocks. Open cooler valve and open air vent
at top or drain cock at bottom of heat exchanger depending on model. With the pump air-tight,
open primer with engine running for about a minute and then close primer. Drain pump of water
which was deposited when heat exchanger and lines were being drained.
Pump not often used for fire service should be inspected and run periodically to ensure that they
will be in readiness for an emergency.
PUMPING SALT WATER
The pump should be flushed out with fresh water immediately after pumping salt water to prevent
excessive rusting. (Except pumps which are built of special materials, such as bronze, to resist the
corrosive action of the brine.)
When measuring sea water with a Pitot Gage, capacities shown in Table No. 2 should be
discounted approximately 1 1/2% to determine the correct capacity.
A centrifugal pump will show 3% higher pressure and require 3% more power when handling sea
water than when handling fresh water if operated at the same speed and capacity.
TESTING OF EQUIPMENT FOR PRACTICE
It frequently happens that operators of fire apparatus, who are not thoroughly familiar with its
operations, become confused under the stress of emergency and neglect some little detail that may
cause trouble or delay in getting the equipment into operation. Therefore, we urge that practice
tests be conducted repeatedly until operators are thoroughly trained. More than one person in the
department should be a competent operator.
Practice should include pumping from low lifts, high lifts with short and long suction lines, with
suction line elevated to form an air trap, and from hydrants, at large and small capacities.
It is important to note the effects of air leaks in hose, insufficient submergence and restriction of
suction line. (Suction line can be restricted by placing a can or other strong closure around the
suction strainer).
NEVER BREAK OR RESTRICT SUCTION OR ALLOW AIR TO ENTER SUCTION LINE WHILE
ENGINE IS OPERATING WITH THROTTLE OPEN. This will release the load and allow engine to
run away.
Do not allow personnel to hold a large nozzle while working at high pressures for serious accidents
may result if hose breaks loose.
MEASURING PUMP PERFORMANCE
Pump performance is measured by the quantity of water it can deliver per minute against a certain
pressure called "Total Head" or "Net Pump Pressure", as it is usually termed in fire pump testing.
The net pump pressure is the sum of the pump discharge pressure, as shown on the pressure
gage with which the pump is regularly equipped, and the total suction lift converted to equivalent
pounds per square inch. If pump is operating from a hydrant, the net pump pressure is the
discharge pressure less the incoming pressure from hydrant measured at the suction entrance of
pump.
Prepared by: EAP
Rev. #3
Approved by: MCR
Date: 1/29/07
5
Revised by: JAF
Revised Date: 5/1/13
1200509
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