Second Hand Herman Miller Aeron Office Chairs - Aeron Adjustments

Seat Height

HermanMillerAeronSeatHeightPaddle-shaped lever on right side.
To raise: While taking your weight off chair, lift lever up.
To lower: While seated, lift lever up.

Goal: Adjust chair height so your feet rest flat on the floor or footrest with your body comfortably supported. Avoid dangling legs, which puts pressure on and restricts the blood flow in the back of your thighs. You may need to adjust your desk or keyboard height to make this work.

Kinemat Tilt Tension

HermanMillerAeronTiltTensionLong stem on right side, with knob.
To increase tension: While seated, turn knob forward (clockwise, toward plus [+] sign).
To decrease tension: While seated, turn knob backward (counterclockwise, toward minus [-] sign).

Goal: Increasing tilt tension gives you more stability and back support when you lean back. How much tension you need in your chair will depend on your body and your idea of what’s comfortable. People who carry more weight above their waists generally need more resistance, people who carry more weight below their waists generally need less. Keep experimenting with it until it’s just right.

Arm Height

HermanMillerAeronArmHieghtWheel on base of arm support.
To raise or lower arms: For each arm, turn wheel upward until arm loosens. Grab the base of the arm support and raise or lower it to the height you need. Turn wheel downward again to lock the arm in place. Repeat for the other side.

Goal: Adjust the height of each chair arm so the weight of your arms are supported. This helps take the weight off your shoulders.

Arm Angle

HermanMillerAeronArmAngleFront of each arm pad.
To swing arms in or out: While seated, grasp front end of arm pad and pivot it to the left or right.

Goal: Getting the arm angle just right helps support different types of work and shifts in posture. Swing chair arms inward for support while using a keyboard. Swing them out when you use your mouse or another input device.

Lumbar Depth

HermanMillerAeronLumbarDepthThick pad on back of chair.
To adjust depth: Putting equal pressure on each end of the lumbar support pad, lift and push it out of its track in the back of the chair. Flip it over and replace it in its track.

Goal: Notice that one side of the lumbar pad is thicker than the other side? Switch between thick and thin sides to find the amount of lumbar padding that comfortably supports the natural curve of your particular spine.

Lumbar Height

HermanMillerAeronLumbarHeightThick pad on back of chair.
To change height: Put equal pressure on each end of the lumbar support pad, and raise or lower it to a comfortable position within the track.

Goal: Adjust it until it comfortably supports your back. You’ll know when you’ve got it right.

Forward Tilt

HermanMillerAeronForwardTiltFront lever on left side.
To position chair forward: Lean back and lift the lever all the way up. Then lean forward with the lever lifted. Release the lever.
To resume horizontal position: While seated, push lever all the way down. Lean back.

Goal: Many people who work on computers prefer a forward-tilting position. To support your back, set the tilt limiter after switching to a forward position. If you work really long hours at a computer, you might try changing from horizontal to forward position every couple of hours to keep your spine healthy and flexible.

Tilt Limiter

HermanMillerAeronTiltLimiterRear lever on left side.
To limit tilt range: Recline as far as you like. Move lever up to define the limit of recline. You can still move forward. Readjust as necessary.
To release tilt limiter: Lean forward, press lever down.

Goal: If you want to sit in an upright position, set the tilt limiter when the seat is in a horizontal or forward position.