Hello,
I am trying to diagnose an air leak in my system.
All three instruments below share the same carrier gas tank:
| Relative abundance | Abundance | ||||||||
| # | Intruments | Inline filter | Water | Oxygen | Nitrogen | PFTBA | Water | Oxygen | Nitrogen |
| 1. | New GC-TQ (HES) | Yes | 1.01% | 0.09% | 0.35% | 41570936 | 420402 | 38728 | 144337 |
| 2. | Old GC-TQ (HES) | No | 6.28% | 20.81% | 77.57% | 760063 | 47728 | 158190 | 589573 |
| 3. | GC-MS (single quad) | Yes (H2O saturated) | 6.70% | 1.00% | 40.65% | 32344 | 4839 | 196224 | |
- System 2. and 3. have air leaks.
- System 2 electron multiplier is aging (max gain factor in autotune report is hovering around 600-900)
- I confirmed the leak is not coming from the MS side of systems 1. and 2. by capping the inlet side of the column and achieving low nitrogen readings.
- Shutting off the gas supply to system 2. and 3. at the EPC resulted in lower nitrogen abundance readings.
- I changed the gas cylinder and the readings are still high
- Used a leak detector to check all swagelok points in the gas lines (there is lot of them) and couldn't find any obvious leaks.
What else can I do to confirm where air leaks are coming from in system 1. and 2.?
