Beckett CG15 - Manual (Page 3)

high CO condition. When the operating control is satisfied the the fuel gas flow will be stopped but
airflow will be maintained for the post/purge interval at the low fire air setting.
• Low-High-Low
Fuel gas flow rate shall be controlled by a diaphragm regulating gas valve or a gas pressure regulator
and a two position fluid motorized valve. Combustion air flow rate for both Low and High fire shall be
controlled with a linkage less damper motor and will be set for the optimum fuel/air ratio for both low
fire and high fire.
A Low-High-Low temperature or Pressure control shall electrically switch the burner to low or high fire
position to meet the system load requirements. The transition from low fire to high fire will be complete
within 4 seconds without any High CO condition. When the operating control is satisfied fuel gas flow
will be stopped but airflow will be maintained for the post/purge interval at the low fire air setting.
• Full Modulation
The main on-off gas supply shall be controlled by either redundant solenoid valves or fluid motorized
valves. The inlet air damper motor shall control the modulated positioning of the air and with a single
linkage to a butterfly type gas proportioning valve to meet varying system load conditions.
The system shall be capable of providing a constant fuel/air ratio, or a linearly adjusted fuel/air ratio, in
order to satisfy individual burner application requirements.
The positioning of the modulating motor shall be controlled by a135 ohm, or 4-20 milliamps, or 0-10
VDC, modulating type temperature or pressure controller.
• Full Modulation w/RWF40
The main on-off gas supply shall be controlled by either redundant solenoid valves or fluid motorized
valves. The inlet air damper motor shall control the modulated positioning of the air and with a single
linkage to a butterfly type gas proportioning valve to meet varying system load conditions.
System response to load shall be controlled by a pressure or temperature controller incorporating PID
logic for optimum system response. The controller shall display the system set point and the current
operating point, and include manual controls for set-up adjustments. The appropriate pressure or
temperature sensor shall be provided with the control.
Burner Control Panel:
(Spec writer –select one of the following)
• All control components shall be mounted and wired on a control box that is mounted on the burner
housing. The control box shall incorporate an Easy Access cover and Power On and Fuel On indicator
lights. All wiring within the control box shall be factory prewired to a terminal strip. The control box
shall have an illuminated rocker switch that will limit the burner to its low fire rate for set-up
adjustments.