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| Boiler Control | One can control a boiler via various methods. Boiler control is the local control on the boiler itself. One sets this control required for maintainance of the necessary boiler set points. Another type of control is an applied system of Direct Digital Control (DDC). Such system uses boiler control strategies necessary for boiler equipment and is more sophisticated comparing with simple systems of control. Complex boiler systems controll multi-stage boilers for boiler lead/lag, boiler lead/lag with demand assist (demand load management), boiler multi-pump rotation/operational sequencing, and domestic hot water boiler services. Among its other functions, there is boiler monitoring and boiler data collection that saves your time. The control of residential boilers is performed via an aquastat; the control of commercial boilers of high power is performed via more complex control systems. There are also boiler control options used only for local boiler controls. The local controls are based on the applied boiler system and customer boiler efficiency demands.
 Multi-boiler staging is the variety of several boilers that are staged on and off, when it is necessary. Some cast iron boilers can be excelently applied for this purpose. Electro-mechanical and/or solid-state controls provide such control. The measurement of solid-state controls are performed via the delta-T of the supply and return and stage the boilers.
• Modulating Control – it depends on the system that reduces the quantity of fuel and air got to the burner. Boiler firing rate can differenciate from low fire to high fire and input temperatures that influence the need for delta T.
On - Off Control – it means that the boiler switches on and increases to high fire and remains at this point up to the moment it is necessary meeting the requirements of a pre-determined set point.
Step-up/Step-down – such type of boiler control provides you with some firing rates that can be added if it is required for heating. It can change to high fire, medium fire or low fire.
Oxygen Trim Control – it measures the quantity of O2 in the flue gases and balance the excess air required for more effective combustion.
Excess Air Regulation Control – it is required for the maintainance of a certain quantity of excess air to fuel ratio to achieve maximum combustion efficiency.
Air/fuel Сross Limiting Control – it is used for the entry of excess air to the combustion process before using excess fuel and while lessening the amount of the fuel the excess air lessens too. Such measures are required for safety and optimal fuel consumption.
Drum Level Control – it can be effectively applied for boiler systems with critical water level in the drum. DDC provides the system with a hot water reset schedule that lessens boiler cycle rate. It is recommended to consult boiler manufacturers or engineers who have valuable boiler experience for choosing the most suitable boiler control.
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