  We consider a scenario of a composite Higgs arising from a strong sector. We
assume that the lowest lying composite states are the Higgs scalar doublet and
a massive vector triplet, whose dynamics below the compositeness scale are
described in terms of an effective Lagrangian. Electroweak symmetry breaking
takes place through a vacuum expectation value just as in the Standard Model,
but with the vector resonances strongly coupled to the Higgs field. We
determine the constraints on this scenario imposed by (i) the Higgs diphoton
decay rate, (ii) the electroweak precision tests and (iii) searches of heavy
resonances at the LHC in the final states $l^+l^-$ and $l\nu_l$ ($l=e,\mu$),
$\tau^+\tau^-$, $jj$, $t\bar{t}$, $WZ$, $WW$, $WH$ and $ZH$. We find that the
heavy vector resonances should have masses that are constrained to be in the
range $2.1$ - $3$ TeV. On the other hand, the mixing of the heavy vectors with
the Standard Model gauge bosons is constrained to be in the range
$\tan\vartheta\sim 0.1 - 0.3$, which is consistent with the assumption that the
Higgs couples weakly to the Standard sector, even though it couples strongly to
the heavy vector resonances.
