Seal Wash baseline jump

[per_oxid]

Hi,
We run ammonia on a waters h-class and we see a small jump in the baseline for every time the seal wash is operated. If we use 1min this jump is seen every 1min. Its a small jump but enough to impact loq if it happens at time where analyte peak is found. We use 3mM HNO3 in 70%meoh as eluent and I would prefer not to disable the seal wash for system durability comcerns. Seal wash is methanol 20-30% . The old hplc system we replaced did not use seal wash.

Anyone seen simmilar effects? Any possible solution?
Disabling seal wash for this method might be an option as we run very few samples around 100 annualy, thats why we did not get dedicated ic system. I am reluctant to not use seal wash for fear of pump wearing out.
I could add that this was seen even when system was new so its not likely a fault with a worn system.

[Perreman]

I've seen similar effects, however not with IC.

We saw a jump in baseline in our HPLC-CAD analysis. We located the issue to our seal wash solution where the quality of the water was not good enough.

[per_oxid]

I've seen similar effects, however not with IC.

We saw a jump in baseline in our HPLC-CAD analysis. We located the issue to our seal wash solution where the quality of the water was not good enough.

Thanks this is possible, but I am thinking that conductivity in seal wash is different to mobilephase that has 3mM HNO3 so maybe a tiny leakage that is within normal is enough to show on conductivity. For UV methods we dont see any signs of the seal wash used. Anyone that use conductivity detector with seal wash on lc that dont see this effect?

Update:
Our peak RT is 4 min so if seal wash is set at 10 min the jump in signal wont interfere with the peak. Fortunately sealwash is synked with injection so it always running seal wash 10min after injection. This is sort of a solution.