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Service Manual
3Troubleshooting (continued)
Gas valve adjustment procedure
If adjustment of the gas valve is deemed necessary, use the following procedures: (Note: The procedures below are model specific.)
CAUTION Under normal operating conditions this valve should not need adjusting.
Model 400
Locate the throttle adjustment screw on the top of the gas valve, see FIG.
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
Figure 3-2 Gas Valve Adjustment: Model 400
THROTTLE ADJUSTMENT
SCREW
Model 501
Locate the throttle adjustment screw on top of the gas valve, see FIG.
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
Figure 3-3 Gas Valve Adjustment: Model 501
Models 601 - 801
Locate the throttle adjustment screw on top of the gas valve, see FIG.
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
Figure 3-4 Gas Valve Adjustment: Models 601 - 801
THROTTLE
ADJUSTMENT
SCREW
(REMOVE BLUE CAP)
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