AAON RQ NextGen Series, Installation Operation & Maintenance

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Other Coil Cleaners
There are many cleaners on the market for
condenser coils. Before using any cleaner
that is not covered in this section you must
get written approval from the AAON
warranty and service department. Use of
unapproved chemicals will void the
warranty.
AAON testing has determined that unless a
chemical has a neutral pH (6-8) it must not be
used.
Beware of any product that claims to be a
foaming cleaner. The foam that is generated
is caused by a chemical reaction to the
aluminum fin material on tube and fin coils
and with the fin, tube, and coating material on
microchannel coils.
Microchannel coils are robust in many ways,
but like any component they must be treated
correctly. This includes cleaning the coils
correctly to give optimal performance over
many years.
Roofing
The cleaning procedures outlined here use
relatively benign ingredients. When working
with a rooftop unit care must be taken to
make sure the chemicals will not adversely
affect the roof coating. Checking with the
roofing supplier/manufacturer is the best way
to proceed. If the roofing
supplier/manufacturer is not available testing
of the chemicals on the roof coating is
recommended.
Commercial roofing material manufacturers
using PVC and EPDM have been contacted
and indicate that there is no problem with any
of the procedures outlined above.
Options
(See back of the manual for maintenance log)
Heating Coils
One or two row hot water and steam heating
and preheating coils can be factory installed.
All valve controls for heating operation are
field supplied and field installed. Hot water
and steam coil connections are spun copper
tube.
Water coils must not be subjected to entering
air temperatures below 3.3 ° C (38°F) to
prevent coil freeze-up. If air temperature
across the coil is going to be below this value,
use a glycol solution to match the coldest air
expected.
Table 18 - Hot Water Coil Connection Sizes
Model (RQ-)
Hot Water Coil
Connection Size
[mm (in.)]
002-006 (22) 7/8
Table 19 - Steam Coil Connection Sizes
Model (RQ-) Steam Coil Connection Size
[mm (in.)]
002-006
54 (2 1/8) (standard coil)/
29 (1 1/8) (preheat coil)
Chilled Water Coil
Four or six row chilled water cooling coils
can be factory installed. All valve controls for
cooling operation are field supplied and field
installed. Chilled water coil connections are
spun copper tube.
Piping, pressure limiting devices,
backflow preventers and all other
safety requirements shall be in
accordance with national and local
codes.
WARNING