Hale DSD - Manual (Page 24)

TPM (if available) very low in order to limit the
incoming pump pressure by dumping water on the
ground before you have discharge hose lines
connected and are flowing water. Then, as you are
able to use the incoming water, the relief valve
control can be moved up to the desired operating
pressure and set as instructed. This technique will
also help you to purge the air from the incoming
hose and the pump before it can get to a
dangerously high pressure.
Use this procedure after the hose is laid, the
apparatus are in position, and the pumps are
engaged. See the “Pumping from a Hydrant”
procedure for setup and engagement instructions
for apparatus receiving pressurized water.
1. Open two discharge gates on all pumps, except
on the pump at the source, to get rid of air
from hose lines and pumps.
2. On each pump, attach the hose lines to one of
the discharges, and leave the other discharge
uncapped (only for trucks without a relay
valve).
3. Watch the intake gauge for a high-pressure
reading. If this is reached, open the gate
controlling the uncapped discharge to remove
excess water.
4. Supply the pump at the water source with
water; prime if necessary. The discharge
pressure must not be over 150 PSI (10 BAR)
or the maximum pressure rating of the relay
hose to start water moving. Use either the
“Pumping From Hydrant” or “Pumping From
Draft” procedures that appear earlier in this
section.
5. When the water reaches the second pump,
close the uncapped discharge gate. Repeat this
step for all pumps until the water reaches the
fire ground.
6. Adjust the throttle on the pump at the water
source for the required operating pressure.
Watch the gauges to avoid cavitation. (The
pump operator at the fire scene will advise all
other pump operators of the amount of water
needed at the fire ground).
7. Adjust the discharge pressure or flow at the
fire scene to supply the lines being used.
8. Observe the gauges carefully, and adjust the
pressure or flow as needed.
9. Shutdown starts from the fire ground pump
and works toward the water source. Gradually
reduce pressure at the fire ground pump until
you can disengage it. Follow this procedure for
every pump in the relay until the pump at the
water source is shut down.
LOCAL TRAINING PROCEDURES MAY
VARY SLIGHTLY FROM ABOVE.
Tandem Pumping Operation From a
Hydrant
1. Using the large intake hose, connect the first
pumper to the hydrant steamer. Open the
hydrant until the pump is primed, then partially
close the hydrant.
2. Position the second pumper intake-to-intake
with the first pumper.
3. Open a discharge to flow water.
4. With the hydrant partially closed, adjust the
throttle on the first pumper until the intake
gauge reads about 5 PSI (.5 BAR)
5. Remove the unused intake cap.
6. Connect the second pumper to the unused
steamer intake of the first pumper, using a
large intake hose.
7. Open the hydrant completely. Both pumpers
pump water to the fire, (refer to the procedure
on “Pumping From a Hydrant”).
LOCAL TRAINING PROCEDURES MAY VARY
FROM ABOVE.