In boiler systems, the device used to limit excessive pressure or temperature is called a

In boiler systems, the device used to limit excessive pressure or temperature is called a

• A. Limit control
• B. Thermostat
• C. Safety switch
• D. Pressure relief valve

Answer: (A)

In boiler systems, the device that automatically prevents dangerous conditions by shutting off the burner when a preset temperature or pressure is reached is called the limit control. It acts as a safety interlock, stopping fuel flow to keep the system from overheating or overpressurizing. A thermostat mainly controls when heat is needed based on room or system temperature, not a safety shutdown. A safety switch or safety relief valve exists for other safety roles, but a relief valve vents excess pressure after it occurs, whereas the limit control actively prevents the condition by stopping the burner. Therefore, the limit control is the device designed to limit excessive pressure or temperature.

In boiler systems, the device that automatically prevents dangerous conditions by shutting off the burner when a preset temperature or pressure is reached is called the limit control. It acts as a safety interlock, stopping fuel flow to keep the system from overheating or overpressurizing. A thermostat mainly controls when heat is needed based on room or system temperature, not a safety shutdown. A safety switch or safety relief valve exists for other safety roles, but a relief valve vents excess pressure after it occurs, whereas the limit control actively prevents the condition by stopping the burner. Therefore, the limit control is the device designed to limit excessive pressure or temperature.