Tactile is selling a €28 mechanical dial with no recommended setting. The TK-04 turns by hand and can be inspected without logging into an account.
An automated home would usually work out which position its owner wanted. This dial waits for them to turn it.
Plainworks uses similar controls in its household products. Manual publishes repair guides for parts customers can reach.
A buyer asked whether zero meant failure. Tactile said it was one of the positions. The buyer set it to zero and waited. Nothing happened until it was turned again.