Which device senses steam pressure?

Which device senses steam pressure?

• A. Aquastat
• B. Thermocouple
• C. LWCO
• D. Pressuretrol

Answer: (D)

The device that senses steam pressure is the pressuretrol. In a boiler system, the pressuretrol monitors the boiler's steam pressure and uses that information to control firing. It has setpoints (commonly a cut-in and a cut-out). When steam pressure is below the cut-in pressure, the pressuretrol allows the burner to fire and raise pressure. Once the pressure reaches the cut-out setting, it shuts the burner to prevent overpressure. Some systems also use a pressuretrol to regulate feedwater to maintain the desired pressure. Aquastats care about water temperature to control boilers or circulators, not pressure. Thermocouples are temperature sensors used for flame sensing and safety, not pressure. Low Water Cutoffs monitor water level to prevent dry firing.

The device that senses steam pressure is the pressuretrol. In a boiler system, the pressuretrol monitors the boiler's steam pressure and uses that information to control firing. It has setpoints (commonly a cut-in and a cut-out). When steam pressure is below the cut-in pressure, the pressuretrol allows the burner to fire and raise pressure. Once the pressure reaches the cut-out setting, it shuts the burner to prevent overpressure. Some systems also use a pressuretrol to regulate feedwater to maintain the desired pressure.

Aquastats care about water temperature to control boilers or circulators, not pressure. Thermocouples are temperature sensors used for flame sensing and safety, not pressure. Low Water Cutoffs monitor water level to prevent dry firing.