I hate this chair! There is only one control item--a lever, and I've never used it at all. Yet my chair is a different height every other week. This morning I found it so high, my feet don't touch the floor and I can't figure out how to lower it! I've moved the lever in and out and every which way, but the chair doesn't budge.
Some old chairs adjusted just by screwing in and out of the central column. Since yours has a lever, this is probably not the case. If you have never used the lever, then we can't be certain what it does, but on most I have used, pulling up on the lever while seated should allow the chair to lower. Pulling up while off the chair should allow the chair to rise. Some I have seen also let you push or pull the lever to lock or allow the back to tilt some. If you have tried this, the pneumatic cylinder may be shot. Likely just need a new chair.
