Trane ACONT900AC43UA Service Manual page 168

Gas Valves
b. Scroll to the right and select "Gas Val Setup".
c. Push the Enter button.
d. Select "MIN" and push the Enter button.
e. When asked "Are You Sure", select Yes, and push
the Enter button.
f. The furnace will now begin the ignition sequence.
g. If pressure switch 1 & 2 learning routines have not
been performed; after successful ignition, the
inducer will go through this operation. (see Inducer
Learning Routine section).
h. Allow 5 minutes to pass before attempting to adjust
the 40% manifold pressure. This will insure that the
learning routine is complete and that the heat rise
is stable.
j. Read the 40% manifold pressure.
k. If needed, remove the low heat manifold adjustment
cover and adjust to obtain the correct manifold
pressure. See Figure 40.
40% (LOW) HEAT ADJUSTMENT: TURN
CLOCKWISE TO DECREASE MANIFOLD
PRESSURE OR COUNTERCLOCKWISE TO
INCREASE MANIFOLD PRESSURE.
l. Use Manifold Pressure Settings Table 8 for the
correct manifold pressure setting in Inches of Water
Column.
m. Once the 40% manifold pressure has been
adjusted; push the Enter button on the user interface.
This will stop the gas valve setup mode and take
you back to the home screen.
GF - D 16
Table 8
Step 3
Setting "MAX" manifold gas pressure
To enter the Gas Valve Setup mode:
a. Scroll down on the user interface to Unit Test.
b. Scroll to the right and select "Gas Val Setup".
c. Push the Enter button.
d. Scroll to the right and select MAX; then push the
Enter button.
e. Select "MAX" and push the Enter button.
f. When asked "Are You Sure", select Yes, and push
the Enter button.
g. The furnace will now begin another ignition
sequence.
h. If pressure switch 2 & 3 learning routines have not
been performed; after successful ignition, the
inducer will go through this operation. (see Inducer
Learning Routine section).