Beckett Aquasmart 7600b sensor problem

rlaggren

FYI. When the standard temp sensor (not the sensor with LWCO incorporated) forces a lockout erroneously.

I installed the 7600b control 5-6 years ago and it has operated perfectly. Recently after doing a boiler cleaning, I needed to replace a couple of nipples above the boiler (previously unnoticed seepage causing exterior rusting - no drips, though) and afterwards, the boiler started and operated perfectly. The next day the control was in lockout.

It appears I caused a problem, even though nothing was done with the wiring and the sensor was never touched. Maybe some very small amount of water splashed into the vertically mounted sensor well, although I did not find any in the well. It's possible - or not. But pretty sure the problem resulted from my work, either the boiler cleaning on day 1 or my work on the piping on day3. Going on the "water theory" pulled the sensor and heated it to 150+ with a heat gun for a couple minutes, twice, figuring to encourage drying in case water got into it along its cable. Reinstalled, the system functioned properly. Next day, lockout again. The replacement sensor from Beckett has solved the problem.

There may be a take away here - don't get those sensors wet, at all. And/or maybe they get overly sensitive to vibration after a few years of service. Neither the sensor nor its wiring was touched until it failed.


Many problems with the combined LWCO sensor have been reported, where that sensor forces a lockout. Beckett has reportedly replaced those sensors immediately for free and the new sensors solve the problem. A bad production run maybe. My problem above seems unrelated to the LWCO issues.

Regards,
Rufus