Shimadzu GC systems (GC-2010, GC-2014, GC-2030 and their GCMS siblings) are famously durable — which means most “instrument faults” are actually consumables, gas supply, or method issues. Before booking a service visit, work through the classic symptoms below. Column and detector specifics vary; consult your model’s manual alongside this guide.
FID will not ignite (or keeps going out)
- Check gas flows first: typical FID stoichiometry wants hydrogen and air in the right ratio at the jet — a clogged jet or wrong flow setting is the usual cause. Measure actual flows at the detector, not just setpoints.
- Moisture at the jet after column changes extinguishes flames — bake the detector and try again.
- A partially blocked jet ignites but produces a noisy, unstable flame; jets are cleanable or cheaply replaceable.
- Verify the igniter coil glows; igniters are consumables.
Baseline drift and wander
- Rising baseline during a temperature programme is column bleed — normal at high temperature, excessive if the column is old, contaminated, or being run beyond its limit.
- Continuous drift at constant temperature points to contamination working through the system: dirty inlet liner, septum fragments, or a contaminated gas line. Change the liner and septum first — they are the cheapest suspects.
- Impure carrier gas or an exhausted gas-line filter/trap causes drift and noise; check trap indicators and cylinder quality.
- Ambient draughts on the detector, or an oven door not sealing, produce slow sinusoidal wander.
Ghost peaks (peaks with no injection, or extras in every run)
- Septum bleed and liner contamination are the classic sources — replace both before deeper diagnosis.
- Carryover from a previous high-concentration injection: run solvent blanks; if ghosts shrink run by run, it is carryover, not hardware.
- Contaminated syringe or autosampler wash solvent — refresh wash vials and check the syringe plunger.
- Backflash from oversized injections condenses sample in cool inlet zones and releases it in later runs — reduce injection volume or raise split flow.
Sensitivity loss
- Leaks are the number-one cause: check septum (count injections — change on schedule), column nuts after thermal cycling, and inlet fittings with an electronic leak detector — never soap solution near a GC inlet.
- A tired FID collector or contaminated detector shows as gradual response loss; detector cleaning is a documented user procedure on most Shimadzu models.
- Split ratio drift or a blocked purge line changes what actually reaches the column — verify with a known standard.
When it really is the instrument
Electronic flow controller faults, dead detector electronics, and mainboard failures do happen on aging units. On GCs past 15–20 years, weigh repair quotes against a tested refurbished replacement — often similar money for a system with newer electronics, current software support, and every consumable freshly changed.
PLC North stocks tested Shimadzu GC and GC-MS systems and modules, tested with real injections and documented chromatograms — ask for the test data on any listing. Browse our tested GC/GCMS systems.