AAON LZ Series, Installation Operation & Maintenance

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the center pin in the locking arm recess,
secure with set screw (11).
Suction Valve
Manual Operation
The suction side valve is designed for use as
a manually operated isolation valve. This
valve is not designed to automatically pivot
as the discharge flappers do.
Locking
1. Loosen suction side set screw (11) to
release the locking handle (3).
2. Rotate the suction side locking handle (3)
so that the handle points towards the
pump to be serviced and secure in the
horizontal position, using set screw (11).
This releases the suction locking arm (4).
Note: The locking handle (3) should only be
rotated towards the pump stopped for service.
The suction valve is designed to prevent the
locking handle (1) from rotating towards the
running pump, as the suction of the running
pump could cause the valve to slam shut with
sufficient force to injure the operator and/or
cause damage to the pump. Do not attempt to
circumvent this safety feature.
3.
Rotate the suction valve towards the
pump to be isolated. The orientation of
the shaft is indicated by the center pin on
the locking arm (4).
4. Loosen set screw (11) and raise the
locking handle (3) so that the cam on the
base on the handle forces the pin of the
locking arm (4) towards the pump to be
isolated. The locking handle (3) should be
raised to between 45 degrees and the
vertical position.
This handle should not be rotated past the
vertical position.
5. Tighten set screw (11) to secure the
locking handle (3) in position.
Unlocking
1. Open the interconnecting valve on the
seal flush line to pressurize the serviced
pump and vent air through bleeder valve
on series 4302. Close these valves once
the pressure is equalized and air removed.
2. Loosen set screw (11) and lower locking
handle (3) to the horizontal position,
secure with set screw (11).
NOTE:
Keep hands and tools away from
suction valve locking arm when freed by
locking handle as differential pressure may
cause arm to rotate quickly with force when
unlocked.
3. Rotate valve to center position so that the
center pin of the locking arm (4) is
located in the recess on the locking
handle (3).
4. Loosen set screw (11) and raise locking
arm (3) to the vertical position, locking
the center pin in the locking arm recess,
secure with set screw.
Care should be taken when
performing procedures 3 and 4. Read
instructions carefully.
WARNING
Care should be taken when
performing procedures 3 and 4. Read
instructions carefully.
WARNING