  Using the proton ordering model modified by taking into account the
dependence of the dipole moments on the order parameter [Vdovych et al, 2014],
we explore the piezocaloric and multicaloric effects in the KH$_{2}$PO$_{4}$
type ferroelectrics, caused by the shear stress $\sigma_6$ and longitudinal
electric field $E_3$. The multicaloric effect is shown to be stronger than
either electrocaloric or piezocaloric effects, especially at temperatures far
from the phase transition.
