AAON RQ-006 - Manual (Page 63)

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consultation with an AAON service
representative.
If induced draft blower/motor assembly has
to be replaced, care must be taken to provide
an airtight seal between the blower housing
and the burner box.
Gas Heat Exchanger Removal
Removal
Disconnect all wiring on the heat exchanger.
Disconnect flex gas lines and pull out of the
way.
Remove screws around the perimeter of the
heat exchanger face plate that connect it to
the unit. Only the outermost screws should
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 gasket 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.
Figure 28 - Gas Heat Exchanger
Attach the heat exchanger to the bulkhead
using the holes around the perimeter.
Connect flex gas lines to the piping on the
heat exchanger. If flexible gas piping in the
unit must be replaced connectors cannot be
reused, only new connectors must be used.
Connect wiring per the wiring diagram on
the controls compartment door.
Purge gas lines to the gas valves at the unit.
DX Cooling
Set unit controls to cooling mode of
operation with supply fans on. Check the fan
for correct operating direction, amperage
and voltage. Check compressor operation,
rotation, amperage and voltage to the unit
nameplate (check the amperage on the load
side of the compressor contactor).
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 should be
checked for leaks before startup.
Leak checking is the responsibility of
the
installing contractor. All
connections should be checked for
leaks
annually after installation.
Failure to leak check could result in
fire, explosion, or other hazardous
situations.
DANGER