Questrion on Degasser vacuum error in UPLC

[dblux_]

The seal wash does NOT pass through the degasser on Acquity systems. Its a 6 channel degasser A1,A2,B1,B2, weak needle wash and strong needle wash that pass through it.

Thanks AA. At least now we know that when littlepumpkin run out seal wash bottle dry, it had no influence on degasser error.

[littlepumpkin]

Thank you all very much for the suggestions.

I let the instrument sit at standby for two days (I mean flow rate sero, no priming, while with the error light blinking). And reset the BSM (it is BSM ). The degasser vacuum dropped to 0.8 psi, and stayed at 0.6-0.8 psi. No error.

We've tried to reset like that from the beginning and repeatedly before the priming and after air-pulling. Every time there was error. Don't know why this time. I assume
1. the vacuum pump was not working properly that it needs a break time? (cuz right before I reset the BSM, the vacuum display was still >4 psi).
2. we have air in the solvent but it needs time to get pulled out by the membrane and the vacuum pump? (But it could not explain why the vacuum display was still >4 psi before I started today. I guess with the error displayed, the panel is not giving real-time value?)

But the good thing is now the seal wash, priming all worked fine. I am running a Glu-Fib through the column to acquire a 20 min data with our standard gradient, waiting for the result now.

The seal wash does NOT pass through the degasser on Acquity systems. Its a 6 channel degasser A1,A2,B1,B2, weak needle wash and strong needle wash that pass through it.

Thanks AA. At least now we know that when littlepumpkin run out seal wash bottle dry, it had no influence on degasser error.

[littlepumpkin]

It turned out to be just a piece of luck.

I was able to ran several samples today and even the end-of-day wash. However when I stared the end-of-day wash, obvious noise came out from the degasser. I guess that was from the degasser pump. Meanwhile, the vacuum didn't decrease: stayed at 0.74 psi. When I came back to check after the gradient, the gradient finished (50% A and 50% B, with 0 mL/min flow rate), but the error msg showed up again: Degasser vacuum HW error. The vacuum was at 1.90 psi.

I reset the BSM. This time the noise from the degasser showed up again, I guess it's when the pump is struggling? And the vacuum didn't go down. Instead, the pressure increased to 2.44 psi.

I guess my degasser pump is not working properly? Cuz this morning it pulled vacuum from >4 psi to 0.7 psi quickly. If that's the case, I guess I should call waters to change the degasser as the pump is incorporated together? Can I just order the parts and change it myself?

I have tried to pull bubbles from the solvent vent A and vent B line, not bubbles were observed if I pull the same rate as the liquid (I can see bubbles but also feel the vacuum if I pull too fast, is that normal?)

Thank you all very much for the suggestions.

I let the instrument sit at standby for two days (I mean flow rate sero, no priming, while with the error light blinking). And reset the BSM (it is BSM ). The degasser vacuum dropped to 0.8 psi, and stayed at 0.6-0.8 psi. No error.

We've tried to reset like that from the beginning and repeatedly before the priming and after air-pulling. Every time there was error. Don't know why this time. I assume
1. the vacuum pump was not working properly that it needs a break time? (cuz right before I reset the BSM, the vacuum display was still >4 psi).
2. we have air in the solvent but it needs time to get pulled out by the membrane and the vacuum pump? (But it could not explain why the vacuum display was still >4 psi before I started today. I guess with the error displayed, the panel is not giving real-time value?)

But the good thing is now the seal wash, priming all worked fine. I am running a Glu-Fib through the column to acquire a 20 min data with our standard gradient, waiting for the result now.

The seal wash does NOT pass through the degasser on Acquity systems. Its a 6 channel degasser A1,A2,B1,B2, weak needle wash and strong needle wash that pass through it.

Thanks AA. At least now we know that when littlepumpkin run out seal wash bottle dry, it had no influence on degasser error.

[dblux_]

...I guess my degasser pump is not working properly? Cuz this morning it pulled vacuum from >4 psi to 0.7 psi quickly. If that's the case, I guess I should call waters to change the degasser as the pump is incorporated together? Can I just order the parts and change it myself?

If you decide to replace degasser better call for service.

[aceto_81]

The seal wash does NOT pass through the degasser on Acquity systems. Its a 6 channel degasser A1,A2,B1,B2, weak needle wash and strong needle wash that pass through it.

Ooops, my bad, I should have walked into the lab to take a look.
I'm sorry for my bad information.

Ace

[Bull76]

Hi,

Sounds like the vacuum pump has indeed met it's maker. You'll need a replacement pump at a minimum. Hope you have a service contract as it is an expensive part for the size and what it does.

When you say pull bubbles from the vent of A and B what do you mean by this? You shouldn't or need to apply a syringe to the vent of the Pumps. Both pumps are more than capable of priming the lines for all four solvents. If when the unit is priming you see the flow fluctuate then you more than likely need the pump serviced. The Acquity was designed to be user friendly but some people asume they can do the same with it as an Alliance.
A little more care and the unit should work perfectly between PM intervals. Seal wash running dry can cause an issue with the seal's in the pump...Just my observation on the the matter.

Regards,
Bull76.

[cdiverson]

I'm having similar problems with my Waters Acuity UPLC, albeit after some time the pump is able to bring the pressure back down to around .65 PSI from 1.9 psi (starting pressure after powering up the instrument after being shut off for a week). After talking to Waters I'm pretty certain the degasser chamber needs replacing. Unfortunately the money isn't there right now to replace it with a new Waters part. Does anybody know where I could get an equivalent part for cheaper or a refurbished degasser? If not, is there a way to bypass the degasser? I don't mind sparging instead, but I know that if it gets to the point where the degasser continually throws a hardware error then I can't use the system in that normal configuration.

[Multidimensional]

Lots of inaccurate info found in this thread. Much of it was due to the use of incorrect terminology or a lack of understanding in how the Waters Injector Wash (seal wash is a completely separate and unrelated system) system and the separate in-line degasser operate. Too many points to address individually, but here are some comments for anyone that finds this post through a search that should help them better understand these issues..

(1) Some of the Waters pump modules do have a 5th or 6th vacuum chamber (e.g. BSM) and the INJECTOR WASH solution IS run through one or more of those degassing chambers to remove dissolved gas from the solution. This is needed because Waters used (and still uses) an older injector design which is low pressure and subject to getting air bubbles in it (or becoming contaminated from use). Degassing the solution reduces, but does not eliminate the problem. It is critical to use this feature and flush it regularly with fresh wash solution or the injector repro will become very bad. High pressure injectors, such as found on HP/Agilent systems since the 1990's do not have this issue.

(2) Waters DEGASSERs:

NEVER leave air inside a degasser vacuum chamber. They must be filled with fluid at all times, even if you are not planning on using one of the chambers. If you do not plan on using one or more channels, please place the solvent pickup lines into their own clean solvent bottle or a bottle you are already using. Then, use those wet positions to periodically flush them out, do not plug them. The liquid inside will quickly evaporate and leave the chambers dry (which is what we must avoid). Failure to maintain the chambers with fluid inside may result in early failure of the vacuum system and/or pervaporation of mobile phase into the vacuum system. This may result in internal contamination of the entire vacuum system (and then failure of the same) plus that same contamination can be passed back into the mobile phase and contaminate your column and analysis.

"

DR wrote:
For future reference - it is never a good idea to try to pull anything into a degasser (unless you know otherwise, for certain that yours can deal with it. There are some old units that can handle this, they typically have a high internal volume - 10mL or more). Many modern degassers can be easily ruined by having a vacuum applied to their outlets.

"

*While it is true to make sure the degasser is chemically compatible with the liquid you wish to use, the above information is incorrect. Always PULL. Never PUSH fluid through the degasser vacuum chambers. Most Waters vacuum chambers are only rated for 10 psi max pressure and may rupture if over-pressured ($$$). Only draw fluid through them (just like your HPLC pump does) when priming or flushing them.

Normally priming of the HPLC vacuum degassing chambers can be accomplished using the HPLC pump to pull or draw liquid, one-at-a-time, through each one. If the system has sat for some time, you may first need to draw fluid down the solvent lines to the degasser module (syringe pulling fluid, not pushing) to help get things started. Allow time for degassing to take place after the chambers have been filled with liquid (usually a few minutes) and remember that the higher the flow rate, the poorer the degassing with these types of system. Degassing efficiency is a function of both available surface area (a fixed value) and exposure time (flow rate = exposure time). Gas will naturally diffuse into the Teflon low pressure solvent lines so degassing is needed all of the time to maintain a constant level of degassing (constant = stable baseline).

The Waters Vacuum degasser pump never "shuts" off. It stays on all of the time and is known as a continuous running, closed loop system. At turn on, when the chambers are at atmosphere, the vacuum pump will run at high speed to pull down the vacuum level near the setpoint. When it gets close, it will slow down and slowly reach an equilibrium in speed needed to maintain the internal vacuum level at the setpoint. This usually takes ~ 5 to 10 minutes total. If the flow rate, amb temperature or the solutions change, the speed of the vacuum pump may also change. If well maintained, the system is designed to work for about 5-6 years. You will see the vac readout on the system and most of them should be between 0.6 and 0.9 psi at the setpoint. Do not assume that if the system fails to reach vacuum that your vacuum pump is bad. It may be, but far more common reason for the vac reading to be high is that air is in the system (as in, the vacuum chambers) because they do not have liquid inside. All vac chambers must be filled with fresh liquid at all times. So before doing anything, flush out all of the vacuum channels, slowly, with fresh fluid and let the system run at a low flow rate (e.g. 1ml/min) for 15 minutes and see if it is now OK. If you have a leak, one or more of the chambers may not be getting filled with liquid. Another reason the system will fail to achieve vacuum is due to old leaky vacuum tubing. The tubing rots and disintegrates over time (it also may become contaminated or attacked by your mobile phase and fail, esp if you have a vac leak inside). Replace the vacuum tubing with fresh high purity tubing every 5 years (do not use "Auto store" tubing, it will contaminate your system!). If the vac chambers are ruptured, then they will have to be replaced.

(3) Degasser Parts: Waters is not the only supplier of factory parts for these units. You can also purchase new factory parts or optionally, professionally refurbished parts for many of these degasser modules for a fraction of the retail price from Chiralizer Services, LLC in the USA (a company that I work for). We have been professionally servicing these modules for most of the major manufacturers and end-users for 25 years and can save you a lot of money by fixing only what is broken vs replacing an entire assembly at greater cost. Professional HPLC degasser repairs, down to the component level with 1-2 business day turnaround time on most repairs. More info here: http://www.chiralizer.com/hplc-degasser-repair.html or http://www.chiralizer.com/uploads/8/9/7 ... s_page.pdf

[fareedtayyeb]

We are experiencing partial display on UPLC Control console. We are using Empower2 2154 with installed 1.65 ICS. MS FrameNet 3.5v. It shows NOT CONNECTED with Red dot on both BSM,ASM also configured by DHCP,MAC address etc. Surprising thing is that our instrument activates Pump and autosampler works still showing not connected sign.
Plz guide from here. Its our first time with Acquity system
Thanks and Best regards

[Multidimensional]

" fareedtayyeb ": Please Do Not Hijack other member' posts. Your post is not in any way related to the discussion thread.

If you have a new question that you wish to ask for help with, then please follow forum guidelines and create a new post with detailed information and member's will try to assist you. Please delete your post here to preserve the discussion. Doing so will keep the information organized to better help other users.

[fareedtayyeb]

Thanx !!! Reason to jump into bcoz f all Acquity experienced people anyway i am posting new post now

" fareedtayyeb ": Please Do Not Hijack other member' posts. Your post is not in any way related to the discussion thread.

If you have a new question that you wish to ask for help with, then please follow forum guidelines and create a new post with detailed information and member's will try to assist you. Please delete your post here to preserve the discussion. Doing so will keep the information organized to better help other users.