high pressure

What is the name of the manufacturer and model of the equipment you are working on? 

check your bellows or air outlet valve(depending on mfr), you have a component failing to open to bleed out air from the chamber. or you could have a bad pressure sensor, or pcb. if it's not a table top(steris century, 300 series, etc) pressure sensor may need a cal, or you could have a valve not opening. what is the make/model of your unit?

The lab uses a VWR AccuSterilizer AS12. 

I think the outlet valve is at the back of the unit but I don't think anyone has tested to see if this releases and reseals properly (we recently relocated).  I'll give it a go and let you know after the weekend.  I also noticed that a small filter/sieve inside of the sterilization chamber had broken off flush with the surface of the chamber (very back, bottom).  Can these be replaced since I don't want material (cotton) going down this port?  I only have the owner manual for this unit and not a service manual. 

Do you know at what part of the cycle it gets this error? During heatup, sterilization, exhaust, drying, etc?

The Elapsed Time was 33:16.  The Temperature was 131 C.  The pressure was 41 PSI. And it was on an Unwrapped Heating.

temp sensor could be dirty or damaged, air bellows might not be opening keeping an air pocket, confusing your temp sensor. @41psi, your temp should be thru the roof. 30psi, 273f is the goal. small 1 or 2 degrees deviation, 1 psi deviation. 

so one of those numbers is wrong.  Do you have aguage or external thermo to verify one of the 2 specs?

We don't have a guage (pressure?) or external thermometer to measure these.  :(