Wiring For Full Modulation; Damper Motor Components - Beckett CG15 Manual

Wiring for Full Modulation

Electric Shock Hazard
Turn off all electric power to the burner before
servicing.
If power is required for adjustments, use extreme care
while working near live conductors.
Figure 23 — Terminal Strip WIring
Terminal Strip
For standard construction burners the junction
box contains a color coded terminal strip showing
connections for control system power (and blower
motor power for 120 VAC blower motors), limit string
connections, gas valve connections, and rate control
connections. The terminal strip markings match the
wiring diagram specific to your burner. All of your
control connections are to be made to this terminal
strip. For burners with blower motors operating at a
voltage greater than 120 VAC the junction box will have
a separate motor contactor section with its own power
connections. Refer to the wiring diagram supplied with
your burner for connection details.
CG15, CG25, CG50 Burner Manual, Form No. 6104BCG50
Color Coded Label

Damper Motor Components

The damper motor positions for high fire and for low fire
are set by adjustment of individual cams in a cam stack
(Shown in Figure 24 ). Only three of the cams in this
motor are active, the red, black and green cams.
• The red cam limits the maximum position of the
motor to the burner's high fire setting.
• The black cam limits the minimum position of the
motor to the burner's low fire setting.
• The green cam could be used to set a third position,
for example an off position for the damper. We do
not use the green cam, but we recommend that it
be set to the same position as the black cam.
Figure 24 — Damper Cam Adjustment
Red High Fire Cam
(Example:Red Pointer
set at 90)
Adjusting
Screws (Example: Green Pointer set at 25)
Figure 25 — Damper Cam Position Scale
Indicating Notch for
Damper Position
Section: Start Up And Operation —
Black Low Fire Modulation
Limit Cam (Example: Black
Pointer set at 25)
Green Low Fire Limit Cam
Damper Position Scale
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