What are boiler lower and upper level limiters?
The function of the lower surface limiter, i.e. the dry boiling sensor, is to shut off the burner of the steam or water boiler when the water level drops too low and thus prevent damage to the boiler or a potential boiler explosion.
In steam boilers, dry boiling protection can be implemented either with two separate self-monitoring sensors (GESTRA NRG) or with three pressure-differential transmitters. By using electrodes designed specifically for this function, problems such as those with impulse lines are avoided.
Choosing boiler lower and upper level limiters
GESTRA dry boiling electrodes are PED-approved self-monitoring models, in which communication between the sensor and amplifier is digital. In addition to the digital models, traditional models with SIL 3 safety rating are still available. The conductivity of the fluid must be at least 0.5 µS/cm. The pressure/temperature rating of the sensors is up to 183 bar(g)/400°C, i.e., PN 320.
GESTRA also offers a SIL 3 rated boiler water upper surface limiter.
We assist you in selecting the appropriate dry boiling protection based on the requirements of the application. Contact our representatives for more information.
