Most Common Sources for Leaks in the MA-3000

Most Common Sources for Leaks in the MA-3000


The internal components of the MA-3000 are at very high temperatures. Please make sure that the instrument is powered off and the temperature is down to room temperature before removing any covers and servicing the instrument.


Since you can only create gas flow through the MA-3000 with the power ON, after it has cooled completely, follow these instructions to prepare for troubleshooting:

1)  After powered OFF and cooled down, remove the top cover of the MA-3000.

2)  Locate the heater board as shown in the picture below:  
This step is not necessary if the instrument has been previously powered off and you are using the "Self Test" function that automatically appears when the instrument is powered on.  This feature is designed such that it will not turn on the heaters until the self-test passes, which includes a leak check.  Thus, there is no concern of the heaters getting too hot while trying to find the leak.



3)  Disconnect the large ribbon cable labeled "Heater" of the left side of the board by first pressing on the clips on each side of the cable's connection port.  They will push down and away from the sides of that connection port, allowing the cable to be disconnected.  Place the cable safely out of the way near the side panel of the MA-3000.

4)  You may now power ON the MA-3000, and it will not heat any of the heaters.  This will allow you to run the Leak Check program in the software.


Be very careful to keep your hands clear of all power cables and wiring along the left side of the MA-3000.  Electrical Shock can occur.

If your instrument is equipped with the humidification kit, this is the most common leak point, try running the leak check while pushing down on the top piece of the humidifier.  You can use parafilm if needed to seel the leak, and or get a new clamp.  Please know that the leak check is the only time that the humidification kit is pressurized.

5)  After checking the humidification kit (if equipped), the first location on the analyzer to confirm is the carrier gas inlet.  Locate the elbow fitting shown in the picture below on the inside of the analyzer near the front next to the H1 heater, disconnect it from the metal pipe, and remove the fitting from the Teflon tubing.



6)  Run the Leak Check program under the Run menu in the MA-3000 software.  Immediately after starting the leak check, place your finger firmly over the end of the Teflon tubing that was connected to this port.  The flow rate should immediately drop to zero, and the leak check will pass.  If it does not, then you have a leak or other issue with the mass flow controller.  If the leak check fails here, then contact AGS Technical Support at support@agssci.com for further assistance.

7)  If the leak check passes step 6, then reconnect the elbow fitting to the tubing and the metal pipe.  We will now test the combustion tube and the gold trap connections.

8)  Disconnect the T-shaped fitting from the end of the gold trap as shown below:



9)  You may need to also disconnect this fitting from the branch towards the optical cell to allow yourself enough room for this test.  Start the Leak Check program again, and this time after clicking Start, place your finger firmly over the end of the gold trap.  The flow rate should immediately drop to zero, and the leak check will pass (proceed to step 10).  If it does not pass, then proceed to step 9a.

      9a)  Disconnect the gold trap from the end of the catalyst tube by removing the Teflon joint.  It is usually best to completely loosen the metal nut on the gold trap side first, then slide the gold trap out of the O-ring and washer inside that metal nut.  Make sure not to lose these parts.  You can then do the same for the nut on the catalyst tube side.

      9b)  Once the gold trap and nut are removed, and the end of the catalyst tube is exposed, run the Leak Check program again, and then place your finger over the end of the catalyst tube.  If the leak check passes, then the leak is in the Teflon joint between the catalyst tube and gold trap.  Remove the catalyst tube and reassemble this joint with the gold trap.  If the leak check fails at this point, then inspect the catalyst tube by carefully removing it.  If it has cracked/broken, this is the cause of your leak.  If the catalyst tube is intact, then the leak is due to the O-ring on the sample fork or the V3 valve.

      9c)  To determine if it is the o-ring on the sample for or the V3 valve, reassemble and install the catalyst tube and make sure all the fittings are tight from the previous steps.  Then remove the Teflon joint from the rear of the sample fork, and place your finger over the metal pipe on the back of the fork and run a leak check.  If it passes, the leak is due to a dirty or faulty V3 valve, please follow these instructions for cleaning the V3 valve.  If it fails at this stage it is most likely the o-ring has a foreign material on its surface preventing it from properly sealing.  If the o-ring looks clean and/or does not look damaged, it could be the z-axis nut has failed. 
      9d)  To verify the z-axis is is not broken, perform a leak check while watching the fork seal into the analyzer from a side view.  If the spring on the fork compresses the z-axis is most likely okay.  If the whole bracket the fork is connected to flexes instead of the spring then the z-axis is broken and needs to be replaced.

10)  If the leak check passes step 9, then reassemble the connection of the T-shaped fitting, gold trap, and branch to the optical cell.  Remove the right side panel of the MA-3000 and locate the elbow fitting connected to the High range optical cell as shown below:



11)  Disconnect the elbow fitting from the end of the High Range (short) optical cell.  Run the Leak Check program again, and then place your finger over the end of the outlet from the High Range optical cell.  The flow rate should immediately drop to zero, and the leak check will pass.  If it fails the leak check, then your leak is located within the optical cell or its connections.  Disassemble and reassemble, taking care that each connection is secure.

12)  If the leak is not found through the above testing, please contact the AGS Technical Support Department at support@agssci.com for further assistance.

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