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Step 2—Prime Condensate Trap With Water
UNIT MAY NOT OPERATE
Failure to follow this caution may result in intermittent unit
operation.
Condensate trap must be PRIMED or proper draining may not
occur. The condensate trap has 2 internal chambers which can
ONLY be primed by pouring water into the inducer drain side
of condensate trap.
1. Remove upper inducer housing drain connection cap. (See
Fig. 46.)
2. Connect field-supplied 1/2-in. ID tube to upper inducer
housing drain connection.
3. Insert field-supplied funnel into tube.
4. Pour 1 quart of water into funnel/tube. Water should run
through inducer housing, overfill condensate trap, and flow
into open field drain. (See Fig. 47.)
5. Remove funnel and tube from inducer housing and replace
drain connection cap and clamp.
Step 3—Purge Gas Lines
If not previously done, purge lines after all connections have been
made and check for leaks.
FIRE AND EXPLOSION HAZARD
Failure to follow this warning could result in a fire, explosion,
personal injury, or death.
Never purge a gas line into a combustion chamber. Never test
for gas leaks with an open flame. Use a commercially
available soap solution made specifically for the detection of
leaks to check all connections.
Step 4—Sequence of Operation
FURNACE MAY NOT OPERATE
Failure to follow this caution may result in furnace operation
stopping and water pipes freezing during cold weather.
Furnace control must be grounded for proper operation, or
control
will
lock
out.
Control
is
grounded
through
green/yellow wire connected to gas valve and burner box
screw.
Using schematic diagram, follow sequence of operation through
different modes. (See Fig. 35.) Read and follow wiring diagram
carefully.
NOTE:
If a power interruption occurs during a call for heat (W),
the control will start a 90-second blower-only ON period two
seconds after power is restored, if the thermostat is still calling for
gas heating. The Amber status code LED light will flash code 12
during the 90-second period, after which the LED will be ON
continuous, as long as no faults are detected. After the 90-second
period, the furnace will respond to the thermostat normally.
The blower door must be installed for power to be conducted
through the blower door interlock switch ILK to the furnace
Fig. 46—Inducer Housing Drain Tube Cap
A99118
Fig. 47—Filling Condensate Trap
A99119
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