Beckett RWF40 CG15 Manuel D’Utilisation

CG15, CG25, CG50 Burner Manual

Clock the meter, correct for pressure and 
termperature to get SCFH and calculate the 
input fi ring rate. Compare the calculated rate to 
the specifi ed input for the boiler found on the 
specifi cation sheets and on the rating plates for 
the burner and boiler. Do not exceed the specifi ed 
maximum input for the boiler. 
Attach a manometer to the manifold test port, clock 
the meter, and adjust the regulated pressure until the 
specifi ed input level is achieved. Refer to Table 3.
Be sure to set the breech or furnace pressure to the 
correct value, since this will have an effect on the 
manifold pressure.

1.

2.

3.

B) At burner start-up  - Note, as soon as the burner 
lights, be prepared to adjust the butterfl y valve to set the 
low fi re rate adjustment.

Monitor the fl ame through the observation port.  If 
it appears to be too rich (yellow-orange fl ame), 
move the butterfl y valve shaft slot setting toward a 
more vertical position.  (This adjustment is made 
by turning the nut holding the spring-loaded swivel 
on the butterfl y valve arm.  If insuffi cient adjustment 
is available by this method the butterfl y valve shaft 
can be repositioned in the arm.  Care must be taken 
to make only small changes.)  
Use a fl ue gas analyzer to check the fl ue gas 
ratings for O

2

 and CO.  Your target should be 4% O

2

 

and CO should be well below 50 PPM. (Note that 
the CO is usually near 0 at 4% O

2

.)  

If the O

2

 and CO levels are not on target, turn the 

low fi re adjustment nut as required to meet the 
target listed in Step 2.
Check the low fi re rate.  Either clock the meter or 
compare the manifold pressure drop to factory 
standards.  Adjust the low fi re cam setting in the 
damper motor (if necessary refer to the Initial 
Air Setting procedure described previously) and 
the butterfl y valve shaft slot position as described 
in Step 1.  Refer to Step 2 in this procedure and 
double check the O

2

 and CO readings.

When low fi re is set, use the modulation controller 
to manually step the burner up to its high fi re rate.
Check fl ue gas O

2

 and CO.  Your target should be 

3% O

2

.  CO should be well below 50 PPM, and is 

usually near 0 for that O

2

.  Adjust the regulated gas 

pressure as required to meet the target.
Check the high fi re rate and adjust the high fi re cam 
setting and regulated gas pressure as required to 
meet the target. (If necessary, refer to the Initial Air 
Setting procedure described previously.)
Using the modulation controller, manually step 
the burner back down to low fi re and verify the O

2

 

and CO ratings.  If the high fi re adjustments were 
signifi cant they may have affected the low fi re 
settings as well.  Refer to Step 4 in this procedure 
to make adjustments as necessary.
Using the modulation controller, manually step the 
burner through its range, stopping at several points 
to check O

2

 and CO measurements.  

After you are satisfi ed with the modulation linkage 
adjustments secure all linkage fasteners and 
continue the start-up procedure.

1.

2.

3.

4.

5.

6.

7.

8.

9.

10.

It is acceptable for a burner with 
linkage control of the fuel to show 

2% variation in O

2

 through the range as long as O

2

 stays 

above the target points.  If the O

2

 drops below the target 

points it may lead to a CO problem.  Moving the damper 
arm position on the damper shaft changes mid-range 
O

2

.  Loosening the clamping screws and moving the 

swivel end of the arm downward increases midrange O

2

, 

upward decreases it.  This change will affect the low fi re 
O

2

 setting, and you’ll need to re-set it.