Chromatography Forum

Hi

In our Varian saturn 2000 GC-MS. I am getting error "Pump Error: Controller fault occured". Our Foreline pump is ok this is related to the diffusion pump. While starting diffusion pump it failes and report "Heater overtemp". The detail message it throws -

"The diffusion pump is reporting a fault: Diffusion pump heater has overheated. if this was true on entry to diagnostics. This fault was reset but is still present. Please correct the problem and try again after the heater has cooled."

I have turned off and allowed to cool and turned on again but it still throw the message. Do I need to reset somehow. Diffusion pump seems not starting up. Any direction to troubleshoot will be appreciated. Thank you

I figured the problem. It was the thermocouple attached to diffusion pump was not resetting back to close the circuit. I took it out and tapped couple of times which reset it. Also checked conductivity between the terminal via voltmeter to make sure.