Bongio 9811X Internal Mechanism – Seems Too Short? Here's How to Fix It

When you have received the new Bongio 9811X cartridge, it may seem too short. In most cases, this is because the extension shaft (or hex shaft) from your old thermostat has not been transferred. Below you can read how to check and fix this easily.

1. Check the old thermostat

Look at the top of your old thermostat to see if you can find a small screw or hex key.

• This screw holds the extension shaft in place.
• Carefully loosen this screw with a matching hex key.

2. Remove the extension shaft

Once the screw is loose:

• You can unscrew or pull out the extension shaft.
• Sometimes there is a grooved knob (ridged brass ring) on top — you can slide it off once the hex shaft is removed.

3. Place the extension shaft on the new cartridge

Take the brass extension shaft from your old thermostat and:

• Slide or screw it onto the new Bongio 9811X thermostat.
• Make sure it is securely fastened with the screw or hex key.

After that, the length of the new cartridge should match the old one, and everything will fit perfectly in the tap.

Tip

Check that all parts move smoothly before installing the cartridge. You can remove any limescale deposits beforehand for a better fit.

Still need help?

Feel free to send us a photo of your old and new cartridge side by side. Then we can take a look and see if there is anything else going on.