Pressure increases during analyzing

[brightsun]

I have just met another problem...

During analyzing, pressure of system increases.

I tried checking my pump to remove dirty, and then checking the column,

I also checked the "suction filter" ( filtering the mobile phase before pumping), but it still exsists.

Please give me some ideas.

Thank you !

[haiedc]

Does the pressure increase only during the analysis or all the time? I mean is the pressure normal when you start a new run?