@Keith L posted:Lionel has told me that the thermistor should be 50,000 ohms +/- 2,500 ohms.
Since mine is measuring at 62,000 ohms, it's failed, and it's causing the electronics to think that the smoke unit is too hot and to shut it down.
As it happens, the thermistor is not available by itself. I need to buy the smoke unit board. But heck, I wasn't looking forward to soldering on the PCB, anyway. I prefer soldering jobs that require less finesse.
If you're saying 62K Ohms is causing the electronics to shut down from heat then doesn't that suggest it's a PTC (resistance rises with increasing temperature)?
50K is an unusually large value for a PTC. For example, DigiKey has 243 choices for a 50K NTC, and 0 (zero) choices for a 50K PTC. Can someone post a photo of the smoke unit board showing the thermistor along with whatever supporting electronics? I realize it's a moot point since replacing the entire board is the only remedy. It's just I find it curious that a circuit with a 50K +/- 5% trips at 62K which can be as little as 20% variation.
