Resource Hub / ChromaBLOGraphy / Even More Technical Service “Red Flags” - GC

Even More Technical Service “Red Flags” - GC

15 Sep 2015

My third installment of Technical Service Red Flags contain six more situations that cause us to pay attention and ask questions.  I hope you find these helpful.

Red Flag

Using a liquid leak detector to locate gas leaks instead of using an electronic leak detector. Or worse yet, using both at the same time.  We have, unfortunately, communicated with many customers who have accidently “sucked” liquids into their electronic leak detector. If this happens, turn off the leak detector immediately. We suggest allowing it to “dry” in a desiccator or bag of rice for several days. If it no longer works (or it does not work well), contact Customer Service or your distributor and order 22655-R or 28500-R (Leak Detector Repair Service).  As you may have guessed, the exact number to provide customer service will depend on whether you have leak detector catalog number 22655 or 28500.

Leak Checking a GC System

Leaving your GC oven temperature at or just above ambient temperature overnight with carrier gas flowing. Moisture condensation can become an issue.

How should I store my GC column?

Trying to analyze light gases and/or water vapor using a GC/MS. When NOT to use (GC) Mass Spec

Using our products for applications other than those they were designed for. While I am sure many of our products have multiple uses, we are a chromatography company and our products were designed for our chromatography customers. We will unlikely know if our product will work for your non-chromatography application, and we cannot be held responsible if it does not work. In summary, use at your own risk.

Using a TCD with helium as the carrier gas to quantitate hydrogen. Experiments have shown that obtaining a linear calibration curve can be difficult, if not impossible.

GC carrier gases, do you really have a choice? (See # 4)

Trying to use our Restek ProFLOW flow meter (# 22656) to measure negative (vacuum) gas flows. This item is only designed to measure flows of clean, dry, non-corrosive gases under positive pressure.  If you need to use a flow meter for vacuum gas flows, select one of our Alicat M-Series Flow Calibrators