Calibration of Geneamp 9700

Hello!

 

I have an old Geneamp 9700 PCR system with a dual 384 block. Recently, I said "Fatal block error".

 

I read some Q/A comment here and found the reason would be the block sensor failure. Actually, the sensor was found broken. And I could find a PT1000 RTD sensor (Heraeus M1020) on the web and replace the old broken. It restored the functionality luckly. I used a temperature verification system to run the diagnosis procedure. It was good - maintained the correct temperature with little variation.

 

However, I felt the ramp rate became slow. When it heat up, the ramp rate became slow at high temperature (near ~90 to 95C). Cooling is still fast, but never reach down to 12C (16C was the lower limit it could achieve). So the result of ramp rate test was 1C/sec for heating and 1.6C/sec for cooling.

 

One reason I could guess was thermal paste than I used to assemble the thermal block (base, peltier elements and block). I think its performance (11.2W/mK, pk-3) should be similar to or better than the original one.

 

Does it look to need new verification? 

I don't have any idea to make new calibration values. Would you give me any advice, please?

 

Best regards,

 

Goonbo