AAON RN SERIES Installation Operation & Maintenance page 47

CAUTION
PVC (Polyvinyl Chloride) and CPVC
(Chlorinated Polyvinyl Chloride) are
vulnerable to attack
chemicals. Polyolester (POE) oils
used with R-410A
refrigerants, even in trace amounts,
in a PVC or CPVC piping system will
result in stress cracking of the piping
and fittings and complete piping
system failure.
CAUTION
Each heat exchanger is equipped
with a refrigerant pressure relief
device to relieve pressure should
excessive condensing
(>675 psig) occur.
require installing
connect and route
outdoors. The relief valve has a 5/8"
male flare outlet connection.
NOTE: Ball valves should be installed in
the condenser water supply and return lines
for unit isolation and water flow balancing.
All manual flow valves should be of the ball
valve design. Globe or gate valves should
not be used due to high pressure drops and
poor throttling characteristics.
Pressure and temperature
recommended in condenser water supply
and return lines for system balancing. These
openings should be 5 to 10 pipe diameters
from the unit water connections. To allow
for mixing and temperature stabilization,
wells in the water piping should extend at
least ½ pipe diameter into the pipe.
by certain
and other
pressures
Codes may
contractor to
relief piping
ports are
CAUTION
Installing contractor is responsible for
properly sizing and installing water
system components. Improper fluid
flow due to valves,
improper pump operation may result
in unacceptable unit operation and
void warranty.
Piping systems should not exceed 10 ft/sec
fluid velocity to ensure tube wall integrity
and reduce noise.
piping, or
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