Depende de quais pontos da cozinha o circuito serve.
Você pode ter circuitos adicionais de 15 A que não consertam superfícies de bancada em uma cozinha, contanto que você tenha dois circuitos de derivação pequenos, como exigido por 210.11 (C) e 210.52 (B) suprindo todas as superfícies da bancada. Eu pessoalmente tenho dois circuitos dedicados de 15 A servindo minha geladeira e lava-louças.
Cláusulas aplicáveis por NFPA-70: 2014 (também conhecido como 2014 NEC):
210.11 Branch Circuits Required.
(C) Dwelling Units.
(1) Small-Appliance Branch Circuits. In addition to the
number of branch circuits required by other parts of this
section, two or more 20-ampere small-appliance branch circuits
shall be provided for all receptacle outlets specified by
210.52(B).
...
210.52 Dwelling Unit Receptacle Outlets
(B) Small Appliances.
(1) Receptacle Outlets Served. In the kitchen,
pantry, breakfast room, dining room, or similar area of a dwelling
unit, the two or more 20-ampere small-appliance branch circuits
required by 210.11(C)(1) shall serve all wall and floor receptacle
outlets covered by 210.52(A), all countertop outlets covered by
210.52(C), and receptacle outlets for refrigeration equipment.
Exception No. 1: In addition to the required receptacles specified by
210.52, switched receptacles supplied from a general-purpose branch circuit as defined in 210.70(A)(1), Exception No. 1, shall be
permitted.
Exception No. 2: The receptacle outlet for refrigeration
equipment shall be permitted to be supplied from an individual branch
circuit rated 15 amperes or greater.
(2) No Other Outlets. The two or
more small-appliance branch circuits specified in 210.52(B)(1) shall
have no other outlets. Exception No. 1: A receptacle installed solely
for the electrical supply to and support of an electric clock in any
of the rooms specified in 210.52(B)(1). Exception No. 2: Receptacles
installed to provide power for supplemental equipment and lighting on
gas-fired ranges, ovens, or counter-mounted cooking units.