AAON RL-240 - Manual (Page 58)

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from the condenser does not enter the
condenser air inlet.
Warranties
Please refer to the limitation of warranties in
effect at the time of purchase.
Condenser Tube Inspection
The coil is leak tested at 450 P.S.I.G. before
shipment. AAON will not be responsible for
loss of refrigerant. It is the responsibility of
the installer to verify that the system is
sealed before charging with refrigerant. If
the unit is operated during low ambient
temperature conditions, freeze protection for
the recirculating water system must be
provided.
Freeze Protection
In order to prevent water temperatures from
dropping below 50°F, this unit is equipped
with a VFD on the fan motors when the
refrigeration system is operating.
Recirculating Water System
Electric sump heaters are available to keep
the sump water from freezing when the
refrigeration system is not operating. An
electric resistance heater is supplied in the
vestibule when sump heaters are selected.
Note: The condenser should not be operated
with the fan on and the pump cycled on and
off to maintain head pressure control under
any conditions. The unit is equipped with a
water temperature controller which varies
fan
speed to maintain sump water
temperature. This unit is not equipped with a
compressor discharge pressure controller for
fan speed modulation and therefore cannot
be operated without water flow.
Pre Start-Up
Do
not start the evaporative-cooled
condenser or compressors without
installation of proper water treatment
chemicals. Contact your local water
treatment expert for correct selection of
water treatment chemical, adjustment of
chemical feed and bleed rates.
Cleanliness
Dirt and debris may accumulate in the sump
during shipping and storage. The sump
should be cleaned prior to start-up to prevent
clogging the water distribution system. Any
surfaces that show contamination should be
cleaned ONLY with a commercial stainless
steel
cleaner to restore the initial
appearance. The inlet screens should be
inspected for foreign material.
Storage
Pumps removed from service and stored,
must be properly prepared to prevent
excessive rusting. Pump port protection
plates must not be removed until the pump is
ready to connect to the piping. Rotate the
shaft periodically (At least monthly) to keep
rotating element free and bearings fully
functional.
For long term storage, the pump must be
placed in a vertical position in a dry
environment. Internal rusting can be
prevented by removing the plugs at the top
and bottom of the casing and drain or air
blow out all water to prevent rust buildup or
the possibility of freezing. Be sure to
reinstall the plugs when the unit is made
operational. Rust-proofing or packing the
casing with moisture absorbing material and
covering the flanges is acceptable. When
returning to service be sure to remove the
drying agent from the pump.
Pump Operation
Before initial start of the pump, check as
follows:
1. Be sure that pump operates in the
direction indicated by the arrow on the