Problems with electrodes - filling up the boiler

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: Hi, : I am Javier, industrial engineer and new in this forum. I would like to appreciate the help you could provide me. : Let me explain my problem I had recently in one of the boilers I have visited. : It is a fire tube boiler designed to work at 10 bar., with is filled up when the electrode placed in a external bottle detects that there is no water above its end. Then an electrovalve its opened until other electrode detects that bottle is filled between its end and the bottom of the bottle. : In this bottle there are 4 electrodes: : 1) Electrovalve opens : 2) Electrovalve closes : 3) Minimum level alarm : 4) Ground electrode : The boiler is designed to work at 10 bar, but actually they are working at 3,8 bar. This causes high turbulences inside the boiler which it can be seen in the visual level. : The problem we have is that electrovalve is continuously opening and closing(around 3 seconds intervals between it is opened and then closed, and vice versa). : We modified electrodes to reduce space between open and close electrode, but we only achieve some few seconds of difference. : We think the problem is due to the low pressure they are working at their boiler, which it causes this high turbulence and hence the irregular working procedure. : However, we have another boiler (next to this one) similar to the previous one, with the same electrodes and the same working pressure, which has no problem in its work. We observe level turbulences, but it does not have an irregular working procedure. : Do anyone had this problem before? Could it be that one boiler has an incorrect drain, and it causes to appear foam (which would do turbulence to be more pronounced)? : Can I associate this problem to the working pressure? : Thank you very much for your help. If I found a solution to this problem, I will post it just to let you know how this problem can be solved if you have to face it some day :) : Javier L.