Boiler Water Level Gauge Design

[martinak]

We have two 900psig steam boilers with older flat glass level gauges. Both gauges have had issues more and more frequently and we're planning to replace them. The existing level gauges are an older design so we're also looking to upgrade and install with the LED illuminators. I've come across two different types of gauges but I'm not too familiar with the positives and negatives to either. One design is a flat glass design which is what we have now, and the other is a port glass design. Considering reliability and operability where do these two designs rank? Does anyone have comparable experiences with both designs?

 

[GenB]

Considered an all sealed electronic flag type from Gems. I'm not sure they have high pressure but there are other .FRS.

General Blr. CA,USA

 

[EvenFurther]

"all sealed electronic flag type" if you're referring to a magnetic flag type, those are not permitted in-place of the gauge glass per boiler code. Direct reading gage glass is required per boiler code (ASME Sec.I PG-60). However by keeping the direct reading gage glass, you can add a magnetic flag type. Magnetic flag type is categorized as a remote level indicator or water level sensing device, suitable for boilers 900 psi and below (ASME Sec.I PG-12.2).

Ported gages are rated for higher steam pressures, and will perform better compared to oblong type gage glass. The type with the square 4 bolt covers work well, STB-3000 Quest-Tec has LED lights.