W2690 HPLC do you need to prime all the lines before running samples?
I run a method on HPLC Waters 2690 and its a gradient that used lines A and B and then D for washdown. I have heard people saying you don't need to wet prime the lines you aren't using so in this case C, but I read another article saying its best practice to prime out ALL the lines as its good for the mixing chamber and mechanism of the instrument. What's best for priming the lines in this case? I normally start by priming the seal wash for about 20 mins, followed by priming the needle wash a few times, doing 40 cycles for Purge Injector, followed by 10 mins each wet prime of A B C and D, then slowly ramp up flow rate to initial conditions and equilibrate for an hour before starting a run.
Any thoughts on this procedure?