For the first use

Hot soapy water - Clean all parts thoroughly using hot soapy water, rinse and let dry.

In between distillations

1. Hot soapy water or Grainfather High Performance Cleaner* - Clean all parts thoroughly using hot soapy water or GF high performance cleaner, rinse and let dry. If there is still discolouration, then proceed to next steps.
2. Create a diluted vinegar solution - half parts vinegar and water. Scrub all components thoroughly. Rinse well. 
3. For internal surfaces that are hard to scrub, distil the half vinegar half water solution. Once the distillate starts coming out, turn off the unit and let it cool. Thoroughly wash all components afterwards.
4. If there are any especially tough stains, dilute 2 Tbsp of citric acid in 4L (1 US Gal) of water and leave to soak for a few minutes. Wash thoroughly and dry.

 *Note, high performance cleaner will not shine or passivate the copper