AAON RZ Series, Installation Operation & Maintenance

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Air Inlet
Inspect the air inlet louvers and mist
eliminators into the condenser section on a
monthly basis to remove any paper, leaves or
other debris that may block the airflow.
Stainless Steel Base Pan
The base pan under the tube bundles is
stainless steel and may sometimes become
tarnished due to contamination.
These
surfaces must be inspected yearly to ensure
they remain clean of any contamination that
may result in damage. Any surfaces that
show contamination must be cleaned ONLY
with a commercial stainless steel cleaner to
restore the initial appearance.
Propeller Fans and Motors
The fans are directly mounted on the motor
shafts and the assemblies require minimal
maintenance except to assurance they are
clear of dirt or debris that would impede the
airflow.
Recommended Annual Inspection
In addition to the above maintenance
activities, a general inspection of the unit
surface must be completed at least once a
year. Remove spray header and flush out.
Cleaning
Mechanical cleaning, including pressure
washing, must never be performed as
surfaces and seals could be damaged.
Chemical cleaning that is safe for stainless
steel, copper, aluminum, ABS plastic and
PVC is the only acceptable means of cleaning
the evaporative condenser. A proper water
treatment program should reduce cleaning
needs.
Do not attempt to mechanically clean the
copper tubing in the evaporative condenser.
Do not use wire brushes or any other
mechanical device on the copper tubing.
Severe damage may result. Contact your
water treatment expert for recommendations
on chemical cleaning procedures.
Warranties
Please refer to the limitation of warranties in
effect at the time of purchase.
Evaporative Condenser Water Quality
Cycles of concentration (the ratio of
dissolved solids in recirculated water to
dissolved solids in makeup), must be
determined and monitored frequently by a
competent water treatment expert.
To limit cycles of concentration to maintain
the water quality, it is necessary to “bleed” a
certain portion of the recirculated water. This
is achieved automatically with a solenoid
valve actuated by a conductivity meter set at
the desired conductivity corresponding to the
desired cycles of concentration. Consult a
water treatment expert who has experience
with evaporative condensers to determine the
desired water quality.
All AAON evaporative condensers are
furnished with a bleed system fitting and
valve to continuously remove a small portion
of the recirculated water to keep the water
quality within the above listed parameters.
This device is located on the discharge side
of the pump. It is important to note that since
“bleed” rate is a function of evaporation rate
(i.e., amount of heat rejected), if the bleed
setting is manual based on design heat load,
too much water will be removed when the
heat load is less that design.
The AAON evaporative
condenser is
equipped with a desuperheater. The
desuperheater coil is located above the
eliminators. Approximately 22% of the total
heat of rejection is accomplished with the
desuperheater. Water usage of the AAON
evaporative condenser is approximately 22%