SANDPIPER MHDF2 - Manual (Page 11)

mhdf2dl6sm-rev1210 Model MHDF2 Page 9
RECOMMENDED WARREN RUPP ACCESSORIES
TO MAXIMIZE PUMP PERFORMANCE:
• Tranquilizer ® Surge Suppressor: For nearly pulse-free flow.
• Warren Rupp Filter/Regulator: For modular installation and service
convenience.
• Warren Rupp Speed Control: For manual or programmable process
control. Manual adjustment or 4-20mA reception.
For more detailed information on these accessories,
contact your local Warren Rupp Factory-Authorized Distributor,
or Warren Rupp corporate headquarters.
PRObLEM
Pump cycles but will not pump. (Note: higher suction lifts require faster cycling speed for priming.)
POSSIbLE CAUSES:
A. Air leak in suction line.
B. Excessive suction lift.
C. Flap valve not seating properly.
D. Leakage at joint of suction manifold or elbow flange.
E. Suction line or strainer plugged.
F. Diaphragm ruptured.
PRObLEM
Pump will not cycle. (Note: Always disconnect air supply to relieve air pressure before disassembling any portion of pump.)
POSSIbLE CAUSES:
A. Discharge hose or line plugged, or discharge head requirement greater than air supply pressure.
(Disconnect discharge line to check.)
B. Spool in air distribution valve not shifting. (Remove end cap and check spool — must slide freely.)
C. Diaphragm ruptured. (Air will escape out discharge line in this case.)
D. Blockage in diaphragm chamber preventing movement. (Shut off air supply and reopen after pressure is relieved.)
PRObLEM
Uneven discharge flow. (Indicates one chamber not operating properly.)
POSSIbLE CAUSES:
A. Flap valve not sealing properly in one chamber.
B. Diaphragm failure in one chamber.
C. Air leak at suction manifold joint or elbow flange one side.
For additional information, see the Warren Rupp Troubleshooting Guide.
TROUbLESHOOTING - For additional information, see the Warren Rupp Troubleshooting Guide.
sembly to the point where visual inspection shows that seat and valve face mate without gap. This is important for dry prime.
However, after priming action has started, valves will function due to differential pressure without concern or trouble.
PILOT VALVE
The pilot valve assembly is accessed by removing the main air distribution valve body from the pump and lifting the pilot valve
body out of the intermediate housing.
Most problems with the pilot valve can be corrected by replacing the o-rings. Always grease the spool prior to inserting it
into the sleeve. If the sleeve is removed from the body, reinsertion must be at the chamfered side. Grease the o-rings to slide
the sleeve into the valve body. Securely insert the retaining ring around the sleeve. When reinserting the pilot valve, push both
plungers (located inside the intermediate bracket) out of the path of the pilot valve spool ends to avoid damage.
PILOT VALVE ACTUATOR
Bushings for the pilot valve actuators are threaded into the intermediate bracket from the outside. The plunger may be removed for in-
spection or replacement. First remove the air distribution valve body and the pilot valve body from the pump. The plungers can be located
by looking into the intermediate. It may be necessary to use a fine piece of wire to pull them out. The bushing can be turned out through the
i n n e r c h a m b e r b y r e m o v i n g t h e o u t e r c h a m b e r a s s e m b l y. R e p l a c e t h e b u s h i n g s i f p i n s
have bent.
WARRANTY:
This unit is guaranteed for a period of five years against defective material and workmanship.