How to replace an office chair gas cylinder (complete guide)

What's actually wrong

The full walkthrough of the most valuable 15-minute repair in office maintenance — applicable to nearly every task chair regardless of brand.

Symptoms

• Sinking chair
• Chair stuck low or high
• Height adjustment unresponsive

The fix, step by step

1. Tools: pipe wrench, rubber mallet, and the new cylinder (universal fit, ~$25–45; verify heavy-duty rating if needed)
2. Flip the chair and separate the base: tap the underside of the mechanism plate near the cylinder taper with the mallet until the seat assembly pops off
3. Remove the old cylinder from the base by twisting with the pipe wrench (grip low, twist and pull)
4. Keep the plastic telescoping dust covers and transfer them to the new cylinder
5. Insert the new cylinder into the base, set the seat mechanism onto the taper, and sit down firmly — your weight locks the taper joints
6. Test height range and lock. Done.

When to skip DIY

Warranty on premium chairs; otherwise this is DIY by design.