Hale Trailer User Manual
Page 39
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Operation - Skid & Trailer
p/n: 029-0810-00-0
O p er atio n
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CAUTION - continued !
STOP THE PUMP AND CHECK FOR AIR LEAKS OR POSSIBLE PROBLEMS. SEE
SECTION 5 “TROUBLESHOOTING,” ON PAGE 47.
9.
When operating from a positive pressure source (e.g. hydrant or relay),
make sure any air is purged from the hose and pump.
CAUTION !
WHEN OPERATING FROM A POSITIVE PRESSURE SOURCE WITH A SOFT SUP-
PLY HOSE, DO NOT DRAW RESIDUAL PRESSURE BELOW 5 PSI (0.4 BAR) OR
YOUR DEPARTMENTAL LIMITS. DAMAGE TO THE HYDRANT, HOSE AND POS-
SIBLY THE PUMP MAY RESULT.
10.
Monitor the intake and discharge master gauges. When the pump is
primed, the intake reading falls below zero (0), and the discharge pressure
starts to increase. You may also hear water splashing on the ground, indi-
cating the pump is primed.
11.
Gradually open the discharge valve until water emerges in a steady stream.
Then open the other discharge valves to the desired setting.
12.
Gradually open the engine throttle until the desired pressure or flow is
achieved.
CAUTION !
DO NOT CAUSE A WHIRLPOOL AT THE STRAINER. THIS ALLOWS AIR INTO THE
PUMP, CAUSING ROUGH OPERATION AND PULSATION. REPOSITION THE
STRAINER OR REDUCE FLOW.
As the throttle is opened, the pressure gauge reading increases with the
engine speed. If the engine speed increases without an increase in pres-
sure, the pump may be cavitating.
13.
If the pump is cavitating, warn personnel that the flow is being REDUCED.
Close the throttle and / or discharges slowly until you operate without
cavitation.
The following can also lead to cavitation:
❑
Large nozzle tips - use smaller nozzle to reduce flow.