Hale 80FC - Manual (Page 49)

49 Pump Ends
p/n: 029-0020-61-0
O p er atio n
❑
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.
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.
❑ Air enters with the water - Air leaks can cause rough operation and an
increase in engine speed without an increase in pressure or flow.
If an air leak is suspected, discontinue pumping - see heading “Trouble-
shooting” on page 71.
❑ Hot water - see Figure F-2: “Lift Loss from Temperature” on page 147.
❑ Low barometer - see Figure F-3a: “Lift Loss from Barometric Reading”
on page 147.
❑ High lift - see Figure F-3: “Lift Loss from Elevation” on page 147.
Note: Also see Section “Appendix F: Cavitation” on page 145.
14. If a pump shutdown is desired while pumping from draft, reduce the engine
speed to IDLE and close the discharge valves.
To resume pumping, open the throttle and discharge valves. If the pump
overheats from continued churning without water flow, open the discharge
valves periodically to release hot water.
15. Set the automatic relief valve according to your fire department policy.
16. To avoid pump overheating, if not equipped with the Hale TRV valve, open
the pump auxiliary cooling system valve, or slightly open a discharge valve.
17. After completion of pumping procedures, gradually reduce the engine RPM
to IDLE speed and close discharge valves. Also see heading “Post Opera-
tion Procedures” on page 51.
Draft Operation Limiting Factors
The effect of raised water temperatures when pumping from a positive pressure
source (i.e., a hydrant) is negligible on fire pump performance. However, when
pumping from draft (static source such as a pond, lake or basin), elevated water
temperature does have a limiting effect.