AAON RQ NextGen Series, Installation Operation & Maintenance

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Gas Heat Exchanger Removal
Removal
Verify that the unit power has been switched
off.
Disconnect all wiring on the heat exchanger.
Shut off all gas valves to the unit.
Remove screws on plate below the door
covering the pipes exiting the heat exchanger.
Remove screws around the perimeter of the
heat exchanger face plate that connect it to
the unit. Only the outermost screws must be
removed.
Pull the heat exchanger straight back and out
of the unit. It may be necessary to remove
some of the control door jambs.
Reinstallation
Ensure that the neoprene isolator is installed
around the perimeter of the heat exchanger.
Insert heat exchanger into opening so that the
back of the main plate is against the unit
bulkhead.
Attach the heat exchanger to the bulkhead
using the holes around the perimeter.
Connect wiring per the wiring diagram on the
controls compartment door.
Purge gas lines to the gas valves at the unit.
Reattach plate over exterior piping
Figure 37 - Gas Heat Exchanger
Electric shock hazard. Shut off all
electrical power to the unit to avoid
shock hazard or injury from rotating
parts.
WARNING
LEAK CHECK GAS PIPE
The gas pipe in the unit must be
checked for leaks before operation
and startup. Unit must not be placed
in operation until a leak check has
been conducted for all gas piping
connections. All connections shall be
checked for leaks annually after
installation. Failure to leak check
could result in fire, explosion, or other
hazardous situations.
DANGER