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How To Install Your Replacement Aeron Chair Cylinder

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Replacing the Shock on Your Aeron Chair

If the seat on your Aeron chair sinks whenever you sit in it, the gas cylinder (a.k.a. gas shock, cartridge, pneumatic, hydraulic, piston, lift) has gone bad.  For installation of your replacement Aeron chair cylinder, you will need:

  • A rubber mallet
  • A pipe wrench
  • A 5/32" Allen wrench
  • lubricant such as WD40

Turn your Aeron chair upside down and rest on a flat surface like a table.  Spray some lubricant where the bottom of the seat mechanism attaches to the cylinder, and where the five-pointed base attaches to the cylinder.  You may want to let the chair sit for a few hours to a day so the lubricant works its way in.  

Take your pipe wrench and wrap the jaws around the cylinder.  Twist the cylinder off (doesn't matter which direction) until it comes loose and remove the five-pointed base of the chair.  You will most likely need to use some force as the cylinder has been in the seat mechanism for years.  If you are still having trouble removing the cylinder, you may need someone to help hold the chair down while you twist off the old cylinder.  Make certain the person holding the chair down is holding it down by the frame of the chair, and not by the chair arms as the chair arms can sometimes snap off.  If you need even more leverage, attach a cheater bar (a metal pipe) to the end of the pipe wrench.  The cylinder will come off!

Turn the base upside down and rest 2 of the legs against a hard surface like a table.  You may want to put a cloth between the table and the base to keep the base from scratching.  Take your rubber mallet and bang out the old cylinder.  If the cylinder still won't come out, try using a hammer for more force, but be sure to take a small block of wood or plastic to absorb the blows between the hammer and the cylinder.  Using a hammer directly on the old cylinder may cause the cylinder to collapse making it harder to remove it from the chair base. 

Once the old cylinder has been removed, place the new cylinder in the five-pointed chair base.  Take the plastic ring, and place it around the new cylinder.  With the chair base and new cylinder attached, take the base and place the cylinder into the seat mechanism.  Turn your chair right side up.  Sit in your Aeron chair and test to see if the chair moves up and down with activation of the lever.  If your Aeron chair moves up and down with activation of the lift lever, you are done!

If your chair does not move up and down with the activation of the lift lever, you will need to tighten the set screw.  You will need a 5/32" Allen wrench.  Please go to 1:55 of the video for instructions to tighten the set screw.  

If your Aeron chair now goes up and down without activating the lift lever, you will need to loosen the set screw.  Please go to 2:45 of the video for instructions.  You will need to remove the plastic cover underneath the seat to expose the set screw.

Here is video for installation instructions for your Aeron chair cylinder:

You can order your Aeron replacement cylinder here:

http://www.officereplacementparts.com/gas-cylinder...

You can also order it in heavy duty for users that are heavier:

http://www.officereplacementparts.com/heavy-duty-g...



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