If you are having problems with your QMS Series Analyzer you can call us at
If you wish to try and fix the problem yourself, the user manual may be useful, and the following troubleshooting guide may be helpful too.
Troubleshooting Guide
1) Problems starting the system
Click here to download QMS Turn On Procedure.
2) When powering on the QMS, the mechanical pump doesn’t pump down
It’s likely your diaphragm pump is vapor locked. With the QMS powered on, turn off both pumps (turbo and diaphragm) and close the two valves (capillary flow and sample inlet). Wait until the turbo pump spins down completely. Then remove the capillary and open the capillary valve. This lets the system vent. You should hear the air flowing into the system. After a few seconds try the turn-on procedure above (#1 of the Troubleshooting Guide).
3) No communication with PC
The most common problem is that a USB port is being used for communication along with an RS-232 to USB adapter that doesn't support 28.8 kBaud. Many RS-232 to USB adapters support 28.8 kBaud. One that many customers use is the UC232R-10 from FTDI (https://ftdichip.com/products/uc232r-10/).
If you are still having trouble your QMS Series Analyzer, your instrument will need to come back to SRS for service. Click here to get an RMA number.
