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Lochinvar WHN110 Outlet Temp Sensor TST20022 / 100208547 Failure

Adolfo2Adolfo2 Posts: 31Member
Had my second “Outlet Sensors Drift / Differential” Lockout-Failure in a little over four years.

Didn’t think much about the first one (after 28 months) as failures happen, but the second one (after 22 months) now has me concerned with leaving the house unoccupied during the winter as the fault can only be temporarily cleared via a manual reset.

Others on HH have shared similar experiences and attributed it to the Tasseron Sensor (TSD91A2) where the internal thermistor connections become intermittent causing a resistive imbalance and subsequent Lockout.

Lochinvar parts department & technical support claim to have no knowledge of these failures although Tasseron confirmed that this is a known issue and that they’ve re-designed the sensor (no recall) due to this. The new & improved sensors can only be identified via a date code > “20-18”

Has anyone here on “THE WALL” received any official service / recall bulletins regarding this issue? Any word-of-mouth from distributors, plumbing suppliers, etc., as I’m not in-the-trade so getting this kind of inside information is an issue.

The two pictures below show the displayed fault code along with the associated “bad” sensor.

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