46
Service Manual
3
Troubleshooting
Gas valve adjustment procedure
If adjustment of the gas valve is deemed necessary, use the
following procedures:
Locate the throttle adjustment screw on the side of the venturi
valve (FIG. 3-2). Using a screwdriver, turn the screw a 1/4 turn
clockwise to decrease CO
2
levels or a 1/4 turn counterclockwise
to increase CO
2
levels. After performing one adjustment on the
valve, follow the Combustion Analysis Procedure on page 45 of
this manual to measure the combustion.
If combustion is still not within the specified range, repeat
the procedure. This procedure SHOULD NOT be performed
more than four (4) times. If after four (4) adjustments and the
combustion is still not within the specified range, revisit the
possible causes in Table 3-5 on page 45 or replace the gas valve.
THROTTLE
ADJUSTMENT
SCREW
IMG00160
Figure 3-2 Gas Valve Adjustment
Summary of Contents for WH 399
Page 47: ...47 NOTES ...
