Trane ACONT900AC43UA - Page 172

GF - D 20
Gas Valves
Figure 45
Step 7
If needed, remove the first stage pressure adjustment
cover and adjust the gas valve’s first stage of heat
pressure adjustment screw to obtain the correct first
stage pressure. (Figure 45). Use Manifold Pressure
Settings Table 11 for the correct first stage pressure
reading in inches of Water Column pressure.
FIRST STAGE ADJUSTMENT: CLOCKWISE TO
DECREASE OR COUNTERCLOCKWISE TO
INCREASE PRESSURE.
Table 11
Step 8
Once the first stage gas pressure is adjusted, select
3 on the right hand side of the communicating Comfort
Control screen using the UP arrow for 3rd stage heat
(Figure 46).
Figure 42
Figure 43
Step 4
Select 1 on the right hand side of the screen using
the UP arrow for 1st stage heat (Figure 43).
Step 5
Let the furnace go through the First Stage learning
routine and have its temperature rise stabilize. The
temperature rise and learning routine will take
approximately two minutes.
Step 6
Read the first stage manifold gas pressure after the
furnace’s temperature rise has stabilized (Figure 44).
Figure 44