Chromatography Forum

Dear all

I often heard that people have a problem with wavey baselines when using an air conditioner in the HPLC lab. We also have this problem. One possibility to solve the problem is to connect the air conditioner and the HPLC with different grids. We checked this and the electrician said that the two devices are not connencted at the same grid. But the baseline waves and jumps are experimentally verified: there is a correlation between the air conditioner and the HPLC.
Thus, we think about a damping device. Does anybody has experiences with such damping devices to solve the mentioned problem ?

Thank you very much

Florian

This might be a problem as systems like AC works in cycles to save power, meaning they have comsumption peaks when needed and only uses the fans when temp is correct.

Another problem might be air flow in the system, that may cause differential temperatures and retention time variation.

Solution for electrical problems could be solved with an UPS - you must access your system maximum comsumption (let's say, 1000 VA), add 25% as a safety degree and use it in the supply line. Computer ones would be OK for LC, but for GC is quite problematic, as it consumes over 3000 VA, meaning a good UPS over 5 kVA - a quite expensive and hard to find stuff!

Any chance that your detector is simplyresponding to the temperature change?