The HBOND term in the potential has been deprecated for a couple decades, and any hbond-spec keywords should not be used.
The default nbond-spec for the C36 protein force field (par_all36_prot.prm) is
NONBONDED nbxmod 5 atom cdiel fshift vatom vdistance vfswitch -
cutnb 14.0 ctofnb 12.0 ctonnb 10.0 eps 1.0 e14fac 1.0 wmin 1.5
In general, these defaults should be used for most solvated simulations, with the notable exception that the electrostatic part (FSHIFT) should be overridden by PME keywords. Rather than clutter up the DYNA command, I generally precede that with an UPDATE command, such as
update cutim 14. imgfrq -1 cutnb 14. inbfrq -1 -
bycb atom vatom vfswitch ctofnb 12. ctonnb 10. -
ewald pme spline order 6 fftx @FX ffty @FX fftz @FX kappa 0.34
(The variable @FX is an integer close to the edge length, required for the PME grid.)
I have posted some more complete examples in the Script Archive forum.