Hi Temp code

An EZ10 autoclave was failing with different error codes. Noticed water pouring back into the reservoir during a cycle, so replaced the solenoid assembly (also replaced the air exhaust solenoid assembly). That issue is now solved and we were able to complete 121C and 134C cycles for a couple weeks. Adjusted the pressure pot for a better pressure reading, and the temperature reading already looks good. During a 121C cycle the temperature wavers between 121-123 C. We occasionally get a HIGH TEMP code and cycle failure. I'm trying to figure out why this is happening. At some point a technician increased the incoming water and leveled the feet. Should I undo these actions? What else might be causing the temperature to increase during a cycle when the chamber is not losing water?

Equipment: Tuttnauer 2540ea (ez10)