  Local measurements of heat flux in Quantum Hall devices can deviate from the
expected equilibrium heat flux due to interactions. We present a model of a
simple mesoscopic device consisting of an Ohmic reservoir contacted by chiral
edge states. In contrast to the well studied heat Coulomb blockade (HCB)
effect, we report the opposite phenomenon, an enhancement of the heat flux
carried by an edge state in the HCB regime due to an additional contribution of
the collective charge mode via the fluctuating potential of the Ohmic contact.
We discuss the thermometry of these correlared states and discuss their
detectability. The enhancement effect is also reflected in modified correlation
functions, which influences the electrical and thermal linear response
coefficients in a tunneling probe measurement. On a technical level, we
introduce a Langevin formalism that elucidates the role of these extra
fluctuations in electrical and thermal transport, both in uniformly heated and
Joule heated devices and argue that our approach has advantages in the latter
scenario compared to the standard $P (E)$ theory. We report a violation of the
Wiedemann-Franz law, which is modified by the external resistance of the
mesoscopic circuit.
