Lochinvar KNIGHT 51-211 - Manual (Page 45)

45
Service Manual
3
Troubleshooting
(continued)
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 increase CO
2
levels or a 1/4 turn counterclockwise
to decrease CO
2
levels. After performing one adjustment on the
valve, follow the Combustion Analysis Procedure on page 44 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 44 or replace the gas valve.
Figure 3-2 Gas Valve Adjustment