Why Thermocouple Welds That Pass a Continuity Check Still Drift After Thermal Cycling
After twelve years of installing and troubleshooting temperature sensors on furnaces, kilns, and process lines, one recurring problem stands out. A newly made thermocouple junction looks solid, passes a simple continuity or room-temperature check, and then the reading begins to wander or offset once the sensor sees repeated heat cycles. The root cause is almost always in the way the hot junction was formed on the portable thermocouple welder.