DSF

I've got one of the classic ST-3042 model machines. Is it normal for the temperature to come up to almost the programmed temp then the machine cool down and then go back up to the temperature, this occurs when it is pre-heating. It also does this while I have a product in the machine. Is this normal or do I need to do a repair of some sort to the machine. Thanks

Mine does the same.

The temp is up and down like a whore's drawers.

It is normal and my own conclusion has been that the temp sensor is far too sensitive.

Yep Same here - Usually get +/- 10 degrees C

I also have this, at +/- 10C. I have also had it, when the temperature is set to 220C, to change up and down, dropping as low as 172C.