I've got a first generation brewtus. A few years ago I put in an Auber PID. It generally works really well, but I've noticed recently that when it heats up in the morning it is way overheating.

It heats to the proper temp on the display, but when I run some water through the group head, all of a sudden the temp has jumped another 40 degrees or so and is super heated. after this initial overheat, it cools back down to the appropriate temperature where it remains until it shuts off.

It seems like maybe the temp sensor isn't working properly, or the water is hotter at certain parts of the boiler? Could it have something to do with the offset of the PID? I also don't think it has always done this so I'm kind of confused.

any help would be great