DENSITY LEVEL ERROR Water level gages and all types of remote level indicators are affected by density level error. This level measure-ment error occurs because the water measured by the device is colder than the boiler water, creating a density dif-ference. This system can be explained and modeled by a U Tube Manometer (Figure 4).
The water density in the external instrument is higher than the steam drum water density. The external measurement instrument will always indicate lower than the True Drum Level. The magnitude of the level error depends on operating pressure and height of the water column. The density of boiler water decreases as operating pressure increases.
Water Levels in Steam Boilers | Spirax Sarco
May 16, 2020 · Recommendation: Top up boiler pressure This error code signifies low water pressure. Add water into the system until the pressure gauge indicates a healthy water level, normally between 1 & 2 bar. If you are having to do this more than once every 2 months or if you can see signs of a leak, instruct an engineer.
Power station boilers Power station boilers usually operate at temperatures of approximately 300 °C. When using differential pressure transmitters or displacers, a measured error of up to 29% compared to reference operatingconditions (without compensation) can occur.
Water level indication applies to steam boilers where the water level can be detected. It includesmost steam boilers, the exception being those of the once through or coil type, where there is no steam drum. In such cases, steam outlet temperatures exceeding a