  We report the results of our experimental studies on the magnetic, transport
and thermoelectric properties of the ferromagnetic metal CoMnSb. Sizable
anomalous Hall conductivity $\sigma_{yx}$ and transverse thermoelectric
conductivity $\alpha_{yx}$ are found experimentally and comparable in size to
the values estimated from density-functional theory. Our experiment further
reveals that CoMnSb exhibits $-T\ln T$ critical behavior in $\alpha_{yx}(T)$,
deviating from Fermi liquid behavior $\alpha_{yx}\sim T$ over a decade of
temperature between 10 K to 400 K, similar to ferromagnetic Weyl and nodal-line
semimetals. Our theoretical calculation for CoMnSb also predicts the $-T\ln T$
behavior when the Fermi energy locates near the Weyl nodes in momentum space.
