We already know that $\Delta U=nC_V\,\Delta T$ which is for constant volume
Now we know that $\Delta H = \Delta U + p\,\Delta V$
so $\Delta H = nC_V\,\Delta T + 0$ (as at constant volume $\Delta V = 0$)
$$\Delta H=nC_V\,\Delta T$$
But I have never such an equation anywhere.