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Low Water Cut-off Sensor RB-122-E Probe Replacement
Recently, due to voltage surge caused by snapped neutral power wire, I lost all of my oil boiler controls. I had to discover it painfully one by one as each of them in the control chain was preceded by the other one.
The first one that was discovered as failed was McDonnell RB-122-E. As I was replacing its electrical part, using picture and the terminals diagram, I didn't want, wisely I think, to mess with the probe assembly. I didn't have a proper tool and material to seal its pipe thread connection. The old probe that is still in use is definitely older than 10 years. A technician who installed the last failed control, 3250 Plus, didn't want to deal with the probe either as, according to him, the probe cavity area can't be isolated, piping wise, and water from the system has to be drained in order to replace the probe. There is only one valve above the probe position but not below it where the pipe goes directly into the boiler. The technician somehow discounted importance of the probe replacement as he said it is only useful in case of a major/catastrophic leak in the system, which, according to him again, is extremely rare.
Should I be concerned about replacing the probe as it is older than 10 year old? Perhaps, 15+. The sensor manufacturer is recommending its replacement every 10 year.