Waters e2695 Only Pumping through Line A

[zhikaining]

Dear Experts,

I recently run into some problems with my Waters Alliance e2695 HPLC.

No matter how I set up the system, it will only pump mobile phase in bottle A. I set mobile phase to be 25% A, 25% B, 25% C and 25% D. However, B, C, and D's mobile phase never moved. Only A's mobile phase is going down.

May I ask for some suggestions?

Thanks!

[tom jupille]

Try pumping 100% A, then 100% B, etc., and actually measure the flow rate each time (time collection in a graduate cylinder). My first guess would be that the B,C, and D solenoids are stuck shut. Second guess would be plugged sinker frits. Third guess would be kinked inlet lines.

[zhikaining]

Thanks Tom,

The Flow rate is accurate. The sinkers are working fine. I am guess maybe the GPV is broken. Do you have any thoughts? Thanks.

[BostonFSE]

Swap the lines (a with B) on the degasser and gpv to confirm bad GPV. Rare to have 3 solenoids stuck. Run 100% water through all if heavy salt usage on b c and d
Also flush degasser chambers or bypass with a union

[zhikaining]

I tried that and got the same results.

Swap the lines (a with B) on the degasser and gpv to confirm bad GPV. Rare to have 3 solenoids stuck. Run 100% water through all if heavy salt usage on b c and d
Also flush degasser chambers or bypass with a union

[tom jupille]

If you don't have confidence in your "wrenching" skills, it's time to get a service tech in.
If you *do* have confidence, open up the pump and switch the solenoids between the A and B channels. As long as you have the B solenoid off, check to see if it's stuck (look at the service manual to confirm the necessary voltage first!).

[zhikaining]

If you don't have confidence in your "wrenching" skills, it's time to get a service tech in.
If you *do* have confidence, open up the pump and switch the solenoids between the A and B channels. As long as you have the B solenoid off, check to see if it's stuck (look at the service manual to confirm the necessary voltage first!).

Thank you. I think it may be better to schedule an on site service.

[DR]

Probably the board that runs the GPV is shot. That happens.
We has one go recently, line C was our line of "choice".

When you set it to do 25% of each line and there's no clicking to be heard, and replacing the GPV does not help, it's that board.

[zhikaining]

Probably the board that runs the GPV is shot. That happens.
We has one go recently, line C was our line of "choice".

When you set it to do 25% of each line and there's no clicking to be heard, and replacing the GPV does not help, it's that board.

Thanks. That is very helpful!

[Peggsy]

G'day Zhikaining

did you solve this problem?

Would like to hear of your progress/outcome.

cheers