Dear all,

In our lab we have thermal desorption on line with gas chromatography coupled to a mass spectrometer detector for VOC identification and quantification in indoor air samples. The GC used is from Agilent Technologies, model 6890N and the mass spectrometer detector is from Agilent also, model 5973. The thermal desorption system was from DANI, model STD 33.50.

We recently bought an ATD 350 to replace the old equipment from Dani Instruments (that worked for almost 25 years) but we are having some (a lot) problems...
Since the day the ATD was installed our baseline has much more noise than the one with the old TD equipment and for temperatures of the oven higher than 200ºC we have an intense bleeding of the column.
Moreover the o-rings in the ATD that 'hold' the tube seems to have a life time really short (about 50 analysis) which is unacceptable for us since it is about one week of work before they are completely damaged.
Does anyone has experience with this?
I would appreciate any help.

Thanks,
Anabela