How to Repair an Office Chair-Ehang Furniture

Repairing an office chair requires selecting the appropriate method based on the specific type of fault. Here are common faults and repair steps:

For the Sihoo C500 Second Generation Deluxe office chair, you need to disassemble the backrest structure first:

Disassembly steps: Use a screwdriver to remove the rear cover, take out the 5 fixing screws, and remove the aluminum alloy cup holder.
Repair focus: Check if the gliding track or the connection point of the bone blocks is worn. If there is a gap, adjust the position of the cup holder or replace the worn parts. If the screws are loose, tighten them again and apply thread-locking adhesive to prevent them from loosening again.

This may be caused by problems with the wheels or the seat plate:

Wheel inspection:
- Place the chair upright and upside down, and observe whether all the wheel feet touch the ground. If the ground is level but the wheels are tilted, check if the wheel feet are damaged (e.g., broken or deformed).
- Wheel replacement: Purchase a new wheel set that matches the original wheel model. Use a screwdriver to remove the old wheels. When installing the new wheels, ensure that the fixing screws are tightened.
Seat plate inspection:
- Place the chair on its side and find the metal seat plate (usually a square black painted steel plate located at the bottom of the seat).
- Check if the connection between the seat plate and the gas cylinder is loose. If the screws are loose, tighten them with a wrench. If the seat plate is deformed, replace it with a new one.

The gas cylinder fails, preventing the height from being fixed. You can use the following methods for temporary repair:

Hose clamp method:
- Slide down the plastic skirt to expose the metal gas cylinder. If the skirt covers the cylinder body, remove it first.
- Wrap a hose clamp around the gas cylinder. You can improve the grip of the clamp by wrapping rubber bands, tape, or sanding the surface of the gas cylinder. Tighten the clamp and test if the chair is stable.
PVC pipe method:
- Measure the diameter and length of the gas cylinder and purchase a PVC pipe of the appropriate size (the diameter should be slightly larger than that of the gas cylinder).
- Use a saw to cut the pipe lengthwise and put it over the gas cylinder. Fix the height through the friction between the pipe and the gas cylinder.

The hydraulic system fails, causing the adjustment to be ineffective:

Check the transmission parts: Place the chair on its side and start checking the hydraulic rod, toggle buttons, and other parts from the backrest.
Replace the pivot screw: If the pivot fixing screw (a 10*1 non-standard screw) is damaged, you can replace it with a standard No. 10 screw. Install a 30-millimeter-long screw (the original one is shorter). If the nut-bolt fit is not qualified, screw a nut onto the bolt and ensure that the screw installation does not interfere with the movement range of the hydraulic rod (you can adjust it by adding washers).

How to Repair an Office Chair