AAON RZ Series, Установка, эксплуатация и обслуживание

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system. This pressure switch is set to close at
3 psi and open at 1 psi.
A sensor measures the water temperature in
the pump discharge line. If the sump water
temperature exceeds 105°F, the cooling
system will be shut down thereby preventing
damage to the evaporative condenser.
If a fault occurs in the evaporative condenser
fan motor VFD, normally closed fault
terminals on the VFD will interrupt the safety
circuit, thereby shutting down the system.
The controls send a 0-10 VDC signal to the
VFD based on the water temperature sensor.
The controls are set to maintain a sump
temperature of 70°F. On a rise in sump
temperature, the controls will increase the
speed of the condenser fans. Conversely, on
a drop in sump temperature, the controls will
decrease the speed of the condenser fans.
An outside air thermostat does not allow the
condenser to operate when the ambient
temperature is below 35°F.
Evaporative Condenser Maintenance
The following recommended maintenance
procedures are basic requirements for normal
operating environments. For severe operating
conditions, the frequency of inspection and
service must be increased. Air containing
industrial and chemical fumes, salt, dust, or
other airborne contaminates and particulates
will be absorbed by the recirculating water
system and may form solutions and deposits
harmful to the products and personnel.
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 Maintenance
Cleaning - Remove oil, dust, water, and
chemicals from exterior of motor and pump.
Keep motor air inlet and outlet open. Blow
out interior of open motors with clean
compressed air at low pressure.
Labeled Motors
- It is imperative for repair of
a motor with Underwriters’ Laboratories
label that original clearances be held; that all
plugs, screws, other hardware be fastened
securely, and that parts replacements be exact
duplicates or approved equals. Violation of
any of the above invalidates Underwriters’
Label.
Fan Motor Maintenance
Same as pump maintenance
Access Doors
If scale deposits or water is found around the
access doors, adjust door for tightness.
Adjust as necessary until leaking stops when
door is closed.
The evaporative condenser doors have an
adjustable fit design. A good seal and fit are
key to avoid leaks. A leak inspection is
recommended during installation and every