AAON LZ Series, Installation Operation & Maintenance

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Mechanical Seal
Mechanical seals require no special attention.
The mechanical seal is fitted with a flush line.
The seal is flushed from discharge of the
pump casing on split-coupled pumps and is
flushed/vented to the suction on close
coupled pumps.
The split-coupled pump is flushed from the
pump discharge because the mechanical seal
chamber is isolated from the liquid in the
pump by a throttle bushing. Because the seal
chamber is isolated, seal environmental
controls such as filters and separators, when
installed in the split-coupled flush line are
very effective, as only the seal chamber needs
cleansing, and will prolong seal life in HVAC
systems.
Do not run the pump unless properly filled
with water as the mechanical seals need a
film of liquid between the faces for proper
operation.
Mechanical seals may ‘weep’ slightly at
start-up. Allow the pump to continue
operating for several hours and the
mechanical seal to ‘seat’ properly prior to
calling for service personnel.
System Cleanliness
Before starting the pump the system must be
thoroughly cleaned, flushed and drained and
replenished with clean liquid.
Welding slag and other foreign materials,
“Stop Leak” and cleaning compounds and
improper or excessive water treatment are all
detrimental to the pump internals and sealing
arrangement.
Proper operation cannot be guaranteed if the
above conditions are not adhered to.
Note
Particular care must be taken to check the
following before the pump is put into
operation:
1.
Pump primed?
2. Rotation OK?
3. Lubrication OK?
4. Pipe work properly supported?
5. Voltage supply OK?
6. Overload protection OK?
7. Is the system clean?
8. Is the area around the pump clean?
Warranty
Does not cover any damages to the
equipment resulting from failure to observe
the above precautions.
Double Check Prior to Startup
CAUTION