Stupid Question about Degasser

[crsimons]

Greetings,

I am new to the analytical community (trained organic/inorganic synth) and was gifted an Agilent 1100 series HPLC for my teaching lab. It has the 1332A degasser but only 2 solvents connected (goes to a binary pump). My question is do I need to put solvents into the C & D vacuum ports for an effective degassing or are they disabled somehow by the system? (receiving the error light after 8~10 mins of attempted pump down).

Thanks!

[M Farooq]

Greetings,

I am new to the analytical community (trained organic/inorganic synth) and was gifted an Agilent 1100 series HPLC for my teaching lab. It has the 1332A degasser but only 2 solvents connected (goes to a binary pump). My question is do I need to put solvents into the C & D vacuum ports for an effective degassing or are they disabled somehow by the system? (receiving the error light after 8~10 mins of attempted pump down).

Thanks!

It is ideal to have solvents in all four lines. You can connect the other two empty lines with some neat solvent such as ACN or methanol even if you are not using them. The de-gasser contains quite delicate gas permeable membranes. I am not sure if they are allowed to become dry.

[kubowicz.tomasz]

Hello

You should always have all 4 degasser lines filled with solvents.
However problem you have (error after 8-10 minutes) is because there is no sufficient vacuum level in degasser. It means that degasser is not working properly.
Your problem can be:
-tubing in degasser. Perhaps it needs re-tightening.
-defective vacuum pump. It needs cleaning or replacing.
-solenoid valve
-pressure sensor
It is not very complicated but if you have never fixed degasser it is better ask for service.

Regards

Tomasz Kubowicz

[crsimons]

Thank you two for the help! Will be ordering the pieces to hook up two more solvents as well as going through the degasser repair reported by Agilent (not enough in the budget for an outside repair).

Casey

[Consumer Products Guy]

We just plug up the threaded ports with plastic plugs if not using those channels.

OK, here's my 2 cents. I've repaired both a 1050 degasser and an 1100 degasser by simply opening up and finding broken or cracked black vacuum tubing, not uncommon. The "real" replacement tubing from Agilent may have a little metal spring inside it, but I've also just cut off a damaged end and re-inserted the tubing, and I've actually purchased vacuum tubing/washer fluid tubing at the auto parts store to fix.

Basically these are a sealed box in which a vacuum is pulled, and gases are pulled off through semi-permeable tubing. You should be able to hear and feel if the pump itself is working; most of the remainder is electronics to sense vacuum and turn off that pump when not needed.

[ATAlR]

If you don't really need degasser ( yu can manually degass) if it is only for teaching purpose you, can disconnect cable that is going from degasser to pump, so you can ad least work, without degasser

[kubowicz.tomasz]

Hello

If you don't really need degasser ( yu can manually degass) if it is only for teaching purpose you, can disconnect cable that is going from degasser to pump, so you can ad least work, without degasser

I know what you mean but it is not solution - you just "cheat" the system. The problem will be when you have pressure spikes because of poor degassing and you start to blame pump for it


Regards

Tomasz Kubowicz

[qfiviera]

We just plug up the threaded ports with plastic plugs if not using those channels.

OK, here's my 2 cents. I've repaired both a 1050 degasser and an 1100 degasser by simply opening up and finding broken or cracked black vacuum tubing, not uncommon. The "real" replacement tubing from Agilent may have a little metal spring inside it, but I've also just cut off a damaged end and re-inserted the tubing, and I've actually purchased vacuum tubing/washer fluid tubing at the auto parts store to fix.

Basically these are a sealed box in which a vacuum is pulled, and gases are pulled off through semi-permeable tubing. You should be able to hear and feel if the pump itself is working; most of the remainder is electronics to sense vacuum and turn off that pump when not needed.

I´ve been having reproducibility problems injecting 5 or less uL in gradient elution mode. Service told me it was the degasser (any other problem you tell me sure it is not the cause, and it says on the manual), and Agilent does not repair it, they told you to buy a new one. I really don´t know what´s broken inside it because service and I didn{t open it. Is it posible to fix a degasser? Where can I look?

[Blazer]

I´ve been having reproducibility problems injecting 5 or less uL in gradient elution mode. Service told me it was the degasser (any other problem you tell me sure it is not the cause, and it says on the manual), and Agilent does not repair it, they told you to buy a new one. I really don´t know what´s broken inside it because service and I didn{t open it. Is it posible to fix a degasser? Where can I look?

What kind of reproducibility problems? Area? Retention time? How much reproducibility are you used to seeing and how much are you seeing now?

Yes, you can fix a degasser, but it might be sound to rule out other issues first.

[ATAlR]

We just plug up the threaded ports with plastic plugs if not using those channels.

OK, here's my 2 cents. I've repaired both a 1050 degasser and an 1100 degasser by simply opening up and finding broken or cracked black vacuum tubing, not uncommon. The "real" replacement tubing from Agilent may have a little metal spring inside it, but I've also just cut off a damaged end and re-inserted the tubing, and I've actually purchased vacuum tubing/washer fluid tubing at the auto parts store to fix.

Basically these are a sealed box in which a vacuum is pulled, and gases are pulled off through semi-permeable tubing. You should be able to hear and feel if the pump itself is working; most of the remainder is electronics to sense vacuum and turn off that pump when not needed.

I´ve been having reproducibility problems injecting 5 or less uL in gradient elution mode. Service told me it was the degasser (any other problem you tell me sure it is not the cause, and it says on the manual), and Agilent does not repair it, they told you to buy a new one. I really don´t know what´s broken inside it because service and I didn{t open it. Is it posible to fix a degasser? Where can I look?

It is possible to be degasser, more so if you use Quat. pump with mobile phase that is highly compressible. But I would before degasser suspect injector or MCGV in Quat pump or SSV if you have installed on Bin. pump.

You can open degasser without problem/fear of breaking it more, at least if you will just look

[qfiviera]

We just plug up the threaded ports with plastic plugs if not using those channels.

OK, here's my 2 cents. I've repaired both a 1050 degasser and an 1100 degasser by simply opening up and finding broken or cracked black vacuum tubing, not uncommon. The "real" replacement tubing from Agilent may have a little metal spring inside it, but I've also just cut off a damaged end and re-inserted the tubing, and I've actually purchased vacuum tubing/washer fluid tubing at the auto parts store to fix.

Basically these are a sealed box in which a vacuum is pulled, and gases are pulled off through semi-permeable tubing. You should be able to hear and feel if the pump itself is working; most of the remainder is electronics to sense vacuum and turn off that pump when not needed.

I´ve been having reproducibility problems injecting 5 or less uL in gradient elution mode. Service told me it was the degasser (any other problem you tell me sure it is not the cause, and it says on the manual), and Agilent does not repair it, they told you to buy a new one. I really don´t know what´s broken inside it because service and I didn{t open it. Is it posible to fix a degasser? Where can I look?

It is possible to be degasser, more so if you use Quat. pump with mobile phase that is highly compressible. But I would before degasser suspect injector or MCGV in Quat pump or SSV if you have installed on Bin. pump.

You can open degasser without problem/fear of breaking it more, at least if you will just look

Quat. pump. Injector and MCGV are OK. I´m going to have a look. Is it posible to see something if you have never opened one?

[ATAlR]

Yes you will see perhaps some lose ore decayed tube, signs of mobile phase, especially buffer salts on leaking tubing. When you'll have it open you can give a run without cover and see (hear) if the valve is clicking and if light is switching to green

[kubowicz.tomasz]

Yes you will see perhaps some lose ore decayed tube, signs of mobile phase, especially buffer salts on leaking tubing. When you'll have it open you can give a run without cover and see (hear) if the valve is clicking and if light is switching to green

Hello

If degasser is working fine first yellow light is on (vacuum is still not reached) and then it should be off (correct vacuum level), pump is off (if it is working in periodic mode). Green light is on power switch not on control LED.

Regards

Tomasz Kubowicz

[ATAlR]

You can also disconnect tubing before the valve and check if you got suction, and if it is OK disconnect later untilyou find the problem