  Following a recent proposal, we consider the most general structure possible
for the Hamiltonian operator associated with the Quantum Isolated Horizon(QIH)
with explanations of the underlying physical motivations. An extensive
thermodynamic analysis with this model Hamiltonian is presented. Considering
{\it fixed} number of punctures, the canonical partition function can now be
written in the usual energy ensemble. Arguing that the known classical results
must follow in the correspondence limit (viz. the equilibrium temperature as
observed by a local observer) the model is fixed, yielding the energy spectrum
of the QIH.
