Chows are very seldom excluded from the game, but by allowing a winning hand consist only of Pungs, Kongs, and a pair, the game is made much more difficult. This makes it more plausible to aim at valuable combinations, e.g. a hand consisting of only one suit, etc. On the other hand, excluding Chows results in deals that often end in a draw.
Four Winds does not prohibit you from collecting or claiming Chows, but you cannot go out having more Chows in the hand than is allowed. Declaring Out on a hand which does not meet the requirements specified is considered a faulty declaration of Out, and the normal penalties are applied.
In the American, Australian and British rules the number of Chows is often limited to 1.
To specify maximum number of Chows allowed in a winning hand:
Note: Limitation on number of Chows does not apply to irregular hands with concealed Chow-like series (these are not considered technically as Chows); however, melded Chows, if allowed in such hands, are considered as Chows and counted normally.
As an alternative to the rule that restricts the number of Chows allowed in a winning hand, you can use the option Limit declarations only to specify the maximum number of times a player can declare Chow during a deal. E.g., if the value is 1, then a player can claim a discard for a Chow once during the deal. Note that this does not limit the number of melded (open) Chows in the winning hand to 1, since a player could well complete another open Chow with the winning tile. This would not be considered as a declaration of Chow, since when going out, the player declares "Out", instead of "Chow". Accordingly this rule does not dictate the number of sequences a player can have in hand, but only the number of times they are allowed to declare "Chow" (utter the word "Chow" to signal that they claim another player's discard to complete an open Chow).
This version of Chow restriction is useful to prohibit players to go out on easy low-scoring hands where most of the sets are Chows that have been formed by claiming discards. At the same time, it encourages players to keep their hands concealed to improve their chances to collect more ambitious hands, but does not prohibit them from going out on well-scoring Chow based hands (e.g., ones consisting of one suit only, or scoring extra for going out concealed).
Note: When this option is used, the exceptions to the restriction of maximum number of Chows allowed in the hand will be ignored and are not available for customization.
Related topics:
Minimum points or doubles/faan/han
Prohibition of mixed suits
Require Limit/Special hand
Exceptions