Last few days we observe periodic alarm DRUM WATER LEVEL HIGH which stops boiler. Water sensing rods were cleaned without success, alarm keeps coming. What may cause such condition? |
If your boiler has a differential pressure transmitter, it is most probably connected to the Boiler Sequencer and has 2 functions:
Its signal used by Sequencer to determine when to start and stop Feed water pump. Over the time sludge accumulates in pipes which connect transmitter to water and steam spaces (Low (left) and High (right) pressure sides of transmitter). This leads to erratic signal sent by the transmitter to the Sequencer. As a result, Feed pump may start and stop in the wrong time and overfill the drum. From time to time it is advised to blow Low and High pressure pipes of transmitter.
Wait for reading to stabilize. If transmitter blow down procedure is not helping, transmitter should be dismantled and diaphragm cleaned as per Maker's manual. |