Review on Rheem SP20172 Flammable Vapor FV Sensor Kit in White - Compact & Reliable Solution (6.7X2.7X9.4 inches) by Sean Powers

Update: There seem to be large manufacturing tolerances. I ordered three, one measured 11 kΩ, another 20 kΩ and a third 46 kΩ, at room temperature 80 degrees. According to the spec, 20k seems correct. 11k is too low and 46k is very close to the 50k trigger point, I sent that back. You can measure them first before replacing them, otherwise you may get another trigger right away. The functional specification for the Thermodisc/Emerson 25 VS sensor states that it sinks at 50k ohms. The temperature response curve in the functional specs states that the sensor operates just below 160 degrees Fahrenheit. Its operating temperature ranges from 32 to 150 degrees Fahrenheit. This means that in a hot climate like Texas, the sensor can only be triggered by normal peak temperatures in the attic. .The functional specifications state that this is a one-time sensor, so if it fails it may need to be replaced. But you can measure whether it's still good. After cooling, it should read between 7 kΩ and 25 kΩ with no fumes. You can reset it if it reads less than 45k ohms, but it will likely work again. After replacing the sensor, you need to reset the valve: 1. Turn off the power to the controller2. Restore Control Power For valves with buttons: 3. Press both buttons until the indicators start flashing, then press 4 in the following order. Left, right, left, left, right, left, right, right For Honeywell rotary valves: 3. Turn on GCV.4. Within 30 seconds of turning on the GCV, turn the Temperature Dial end-to-end 7 times. LOW to VERY HOT is a count. Back to LOW is a two count. Unit tries to start - you must complete all seven accounts!5. The device should work normally.6. Set the dial to the desired temperature.