TP-21 HHH Reading Follow
My TP21 is giving me issues, it is reading HHH.
If your device is fairly new there's a chance that a probe would display the HHH code reading on your monitor. Try reinserting the probe as FIRMLY/HARD as possible back into the device until a "click" is felt/heard, that is the probe locking in. Once completed, the HHH error will go away and it will show a temperature.
If you had a flare up recently and the probe came in contact with the flame, it is possible that the probe will show the HHH error code. In that case the probe will need to be replaced.
- This only applies to food thermometers and not household thermo/hygrometers.