couple Questions:
424.3 Branch circuits Allows 15/20/25/30.
Electric heat Thermostates come as high as 22 amps as far as I see. So over 20 Amps Contactor required.

Thermostate rated 125 & of load (unit Switch as disconnect 424.20) =
Off position / two poles Located per 424.19.Within sight of heater OR breaker lock on branch circuit breaker rated 125% of Load.

Another words if a Heater is Not within sight of the ther.
there must be a Fixed breaker lock on breaker feeding that circuit.

Ther. Must be 2 pole , rated 125% of load, Off position,
not over 20 amps without a contactor, within sight of heater unless breaker lock on circuit breaker.

Whatca Think Guys??

Yoop:

Most (if not all) BB Elec heta I installed was with LV t'stats and contactors w/12/24 volt coils. That method of control for simplicity and installation ease.

The LV t'stat & contactor always worked out to a less costly install for me, and it allowed larger loads to be controlled by a t'stst.

The answer to your question IMHO is 'Yes'...2 pole, off position, 125% rated, within site....or a breaker lockout.