Carlin 702GAS Inst Manual - Manual (Page 20)

Model 702GAS Advanced gas burners — Instruction manual
Carlin part number MN702G Rev. 03/14/11 – 20 –
Where appliance instructions differ from this manual, follow the appliance instructions.
All installations should be checked after one to two weeks of
operation to ensure the appliance/burner units are operating
correctly.
14. After the gas pressure regulator has been set, check the gas input, if desired,
by using the gas meter. If input rate is not acceptable, adjust the combustion
head and/or gas pressure regulator as described in the following to provide
for increased or decreased input.
15. The combustion head adjusting screw is used to set the spacing between
the retention ring and throttle ring, regulating how much air passes around
the retention ring. (See Figure 16, page 17.) The larger the value of dimen-
sion A, the larger the clearance, so the larger the airflow. The smaller the
value of dimension A, the smaller the airflow.
a. To reduce air flow, for a lower gas input, adjust the head adjusting screw
to reduce dimension A. Then adjust the gas pressure regulator until the
CO
2
is acceptable.
b. To increase air flow, for a higher gas input, adjust the head adjusting screw
to increase dimension A. Then adjust the gas pressure regulator until the
CO
2
is acceptable.
c. Reset overfire draft to -.02 inches w.c., or as specified in the appliance
manual, after any airflow adjustment. Then verify combustion.
7. Adjust the burner using test instruments
(continued)
Smell around the gas train and check all joints with
a soap suds mixture to ensure the gas train and all
components are tight and leak-free. Shut down the
burner and correct any leak immediately. Failure to
comply could result in severe personal injury, death
or substantial property damage.
Step 4
Set butterfly gas valve linkage
1. Switch the low-fire switch to low fire.
2. Check CO
2
and CO. The CO
2
should be between 9.0% and 10.0%
(natural gas) or between 10.0% and 11.2% (propane); with CO less than
100 PPM.
3. To adjust the low-fire air (change CO
2
), move the burner fuel selector
switch to OFF.
4. Adjust the butterfly gas valve linkage as described in the following to change
the low-fire gas flow to the burner head.
5. DO NOT change the main gas pressure regulator setting.
6. Do not adjust the low-fire air damper setting.
7. See Figure 18, page 19, for location of linkage components.
6. Raise the damper motor linkage by pulling up on the damper linkage locknut
and hold in this position.
7. Loosen the two hex head screws on the butterfly valve linkage arm boss.
Then lower the damper linkage to the low fire position with the damper
linkage locknut. Release the locknut.
8. Mark the position of the butterfly valve linkage arm swivel joint locknut with
a pencil or felt-tip pen. Then loosen the swivel joint locknut.
To adjust the linkage, move the swivel joint locknut in small
increments. A 1/8-inch move can cause CO
2
to change as
much as 1.5%.
• If more gas is needed (to increase CO
2
), move the swivel joint to the RIGHT.
• If less gas is needed (to decrease CO
2,
), move the swivel joint to the LEFT.
9. Tighten the swivel joint in place.
10. Raise the damper motor linkage by pulling up on the damper linkage
locknut and hold in this position. The butterfly valve shaft slot
must be horizontal. If not, use a common-bit screwdriver to rotate
the valve slot to horizontal.
11. Tighten the two hex head screws on the butterfly valve linkage arm boss.
Then lower the damper motor linkage to the low fire position.
12. Restart and repeat as necessary until CO
2
and CO are acceptable per
Table 6.
The linkage between the damper motor arm
and the air damper crank is set at the factory,
and should ONLY need adjustment if the damper
motor or the damper rod is replaced. With the burner
in high-fire position, there should be minimal play
in the connecting rod. DO NOT change this linkage
setting.