A sine wave on the chromatogram is typically caused by fluctuations in temperature.

Please ensure the HTEC door is closed securely.

If the system is placed close to an air conditioner, heater, or other drafts please move the system.  

The HTEC’s temperature control sometimes shows small oscillations, even with the HTEC door latched. Please confirm the ECD has silicon tubing and a reference electrode cover installed as they are by default. 

If those are installed correctly and the baseline oscillation persists, please raise the temperature up for 1 degree.

If your reference electrode is over a year old, we recommend replacement.

If the reference electrode is relatively new but has the sine wave, please wrap the glass part of the electrode with a sponge for insulation.  (Eicom provides the insulation material made with plastic for free, please contact us for this part.)