  A search for charged Higgs bosons produced in vector boson fusion processes
and decaying into vector bosons, using proton-proton collisions at $\sqrt{s}=$
13 TeV at the LHC, is reported. The data sample corresponds to an integrated
luminosity of 137 fb$^{-1}$ collected with the CMS detector. Events are
selected by requiring two or three electrons or muons, moderate missing
transverse momentum, and two jets with a large rapidity separation and a large
dijet mass. No excess of events with respect to the standard model background
predictions is observed. Model independent upper limits at 95% confidence level
are reported on the product of the cross section and branching fraction for
vector boson fusion production of charged Higgs bosons as a function of mass,
from 200 to 3000 GeV. The results are interpreted in the context of the
Georgi-Machacek model.
