  We find the charge and heat currents caused by a temperature difference
applied to a superconducting point contact or to a quantum point contact
between a superconducting and normal conductors. The results are formulated in
terms of the properties of the electron scattering matrix of the quantum point
contact in its normal state, and are valid at any transmission coefficient. In
the low-transmission limit, the new theory provides reliable results, setting
the limits for the use of the popular method of tunnel Hamiltonian.
