You should consider cleaning your ceramic Kamado grill around twice a year to keep it well maintained.
The first stage is to set up the fire to heat up the grill, as this will start the self cleaning process.
Set the heat deflector rack in place, then set the grill on top of the heat deflector. In this example we are also going to drop in a pizza stone to clean as well (only applicable if you have this available).
We are now going to bring the temperature up to about 350 C (650F) or 370 C (700F) degrees and then hold it there for about a half an hour, so make sure your vents are open.
Once you hit the target temperature, leave it for an additional 30 minutes. After that time is reached, close all the vents and let it cool off overnight.
When the BBQ has cooled (after checking temperature),open it up.
Removed all the accessories, and the heat deflector rack from the bottom, you should start removing all the remaining charcoal.
Next, carefully lift out the ceramic fire ring followed by the fire box.
Now scrape out and remove the remaining ash. You can use a stiff bristle brush to brush out the inside walls along with the fire ring and fire box.
You can also use a vacuum cleaner (one suitable for work environments) to remove any remaining dust and ash from both the grill and the ceramic sections you removed.
Next start carefully putting back the firebox and the fire ring (make sure you line the holes up). Then place the deflector plate back and give it one final brush off.
Finally make sure you check the lid bands for tightness.