Final answer:
In a heating system with modulating control, the firing rate can be manually controlled using a modulating control valve operated by a manual control lever or knob on the control panel. Other components on the control panel, such as setpoint adjustments and a display panel, allow for further manual control and monitoring of the system.
Step-by-step explanation:
In a heating system with modulating control, the firing rate can be manually controlled using a component known as a modulating control valve. The control valve is typically operated by a manual control lever or knob on the control panel.
The control panel of a heating system with modulating control usually has several components that allow for manual control of the firing rate. These may include:
- Manual Control Lever/Knob: This component allows the user to adjust the position of the control valve, thereby controlling the flow of fuel or heat input to the system.
- Setpoint Adjustments: The control panel may also have setpoint adjustment controls that allow the user to set the desired temperature or firing rate. These adjustments can be made using buttons, knobs, or touchscreens.
- Display Panel: The control panel often features a display panel that shows the current temperature, setpoint, and other system status information.