Cleaning The CO2 Regulator Cap
Do not submerge the CO2 regulator cap when cleaning, or use PBW or other chemicals. A quick rinse of the bottom of can (area contacts beer) is all that is necessary, or better, just wipe with a wet towel. Rinse body, drain upside down. Do not store with cap on.
Ball Lock Post, Ball Lock Coupling, Hose, Picnic Tap.
These components are all standard, and common with Corny kegs popular with Homebrewers. Component Replacements, or if you would like to modify the tap system, are readily available at your local homebrew shop or online. In addition, there are many YouTube videos on how to dismantle, clean, lube gaskets, etc. for the Ball Lock Post and Ball Lock Coupling.
There is one custom fitting between the Growlveller base and the Ball Lock Post.
This fitting is round, may or may not detach when using a crescent wrench to unscrew the Ball Lock Post (Picture #2, shows Ball Lock post attached to custom fitting base. The base unscrews from the post.)
In general rinsing is all that is necessary. With the picnic tap open filling the Growlveller with water will allow gravity to drain it out the tap and rinsing the system. If you want a more forceful push, some residual gas from a C02 cartridge will work.
The Hose is connected to the Ball Lock Coupling by a threaded connector. This will detach easily to thoroughly clean the hose. A small crescent wrench is probably necessary. Just be careful when re-attaching to the plastic Ball Lock coupling to have just enough force to seal completely, but no use so much strength as to crack the plastic coupling.