Making a Utility CO2 Line Using Luer Lock Disconnects

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What are Luer Lock Disconnects?

Luer Locks are a generally inexpensive and effective disconnect system.  I think these are typically used in the healthcare industry, Luer Locks provide a solid, pressure capable connection with a quick twist.

Valved/Quick Disconnects vs Disconnects

Luer Lock connectors are not what I would call “quick disconnects” meaning that they are not valved to allow easy disengagement while pressure is turned on.  You need to turn off CO2 pressure to disengage these.

Tip: If you’re using these for kegs, disconnect the ball lock gas QD before you disconnect your Luer Lock.  This will prevent the keg from emptying itself of CO2.

A Hybrid Approach

Of course you could use all valved QDS or all Luer Locks in your kegerator setup.  I use a hybrid approach.

Valved QDs for most of my keg lines and Luer Locks to operate a “utility” CO2 line.  One of my CO2 lines has a female Luer Lock on it.  I have a selection of attachments that consist of: The attachment, 5 inches or so of CO2 line and a male Luer Lock.

With this setup I can easily swap out more specialized attachments that I don’t typically need to be hooked up all the time.  Since Luer Locks are generally cheap, this setup saves a good bit of money vs and entirely valved QD approach.

My attachments include (from top to bottom in the picture above):

  • A picnic tap.  I put a length of tubing on the end of this and use it to flush receiving vessels with CO2.
  • A Cornelius gas quick disconnect: Use this line to pressurize and serve a keg as you would any other line.
  • A Cornelius liquid quick disconnect: Use this line to flush a keg with CO2 from the bottom up through the liquid out dip tube.
  • A standard 1/4″ female flare fitting.  I use this to hook up my Blichmann Beer Gun among other things.
  • A Ball Lock Cornelius post.  When I transfer from my fermenter or from keg to keg, this attachment allows me to purge the entire length of tubing, disconnects and the receiving keg (from the bottom up) via the liquid out dip tube.  I used several fittings to accomplish this, but an easier and cheaper option is now available.  See below.
  • A Kent Soda Cap disconnect.  Kent Systems QDs at MoreBeer

Other options include:

  • An air compressor blow gun to flush our carboys and more with CO2 (I’m using the aforementioned picnic tap for this)
  • A length of CO2 line to easily extend your CO2 runs.
This is a picture of the CO2 line I use with these utility attachments.


Luer Lock Connectors:

These Luer Locks are made by Cole Parmer.  They feature 1/4″ barbs to connect to compatible tubing.  I asked the manufacturer for the PSI rating of these disconnects.  I was told… “Thank you for your email. the fittings AO-45502-20 and AO-45505-19 are male and female fittings and compatible. The Psi rating for these fittings together is 100PSI”.

Note: These are not the exact Luer Locks I use.  They’re very similar but from a different manufacturer.  The ones I used seem to have been discontinued.

Tip: In my experience it can be difficult to get tubing onto Luer Locks.  If you have this problem, try soaking your tubing in warm/hot water.

Other parts that may be helpful:

Valved QDs:

A Newer Option – DuoTight Fittings

The system features easy to use push to connect fittings compatible with EVABarrier lined tubing.  Clamp-less installation and reconfiguration.  DuoTight’s  general low cost and versatility out-date the need for something like a utility line.

What should you do?  If you have a conventional setup that you’re going to keep… I’d suggest making a utility line.  If you’re just setting up a kegerator or keezer or are looking for an upgrade.  DuoTights are worth a hard look.

Make sure the components you use are compatible and rated for your intended application.  Contact manufacturer with questions about suitability or a specific application.  Always read and follow manufacturer directions.

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4 thoughts on “Making a Utility CO2 Line Using Luer Lock Disconnects

  1. Anonymous

    Great Tip! I bought me some and set it up air tight and do not even need to use clamps. Works great for me.


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