Use the historical sensor notice only for the sensor and controller it describes.
Electrical access and testing are for a qualified electrician. Isolate all involved circuits and verify they are de-energized before opening boxes, disconnecting conductors or measuring resistance. Energized voltage measurements require appropriate electrical safety precautions.
The linked OJ notice, “Work around ETOG with ETO2 controller,” describes a specific temperature-sensor problem. Its test separates the sensor’s own heater from the temperature measurement: after the heater is disconnected, allow several hours for the sensor to reach the surrounding ground temperature, then measure the isolated temperature pair.
The notice gives reference values of 30 kΩ at 5°C (41°F) and 36,276 Ω at 0°C (32°F). These values belong to that legacy ETOG notice; they are not the ETOG-56 curve. Record the actual sensor temperature, wiring and readings before drawing a conclusion.
The notice also describes an ETF outdoor-sensor configuration as a workaround. Apply it only when WarmlyYours/OJ service confirms that the exact installation matches the notice. Do not change sensor types or bypass a failed input as a general troubleshooting step.
A resistance result does not establish whether damage arose during installation or manufacture, and it does not determine warranty eligibility. Retain model/serial information and installation records for the service assessment.
Sources: OJ legacy ETOG/ETO2 service notice and ETO2 installation manual.