  Quantum superconducting circuit with flexible coupler has been a powerful
platform for designing quantum thermal machines. In this letter, we employ the
tunable coupling of two superconducting resonators to realize a heat valve by
modulating magnetic flux using a superconducting quantum interference device
(SQUID). It is shown that a heat valve can be realized in a wide parameter
range. We find a consistent relation between the heat current and quantum
entanglement, which indicates the dominant role of entanglement on the heat
valve. It provides an insightful understanding of quantum features in quantum
heat machines.
