I. An OWHH that is specifically designed to burn wood pellet fuel with metered fuel and air feed and controlled combustion engineering, which is operated according to manufacturers' specifications and burns only wood pellet fuel shall be exempt from this chapter.
II. An OWHH whose design gross heat input equals or exceeds 2 million BTU/HR shall be exempt from this chapter and shall be subject to permitting requirements under RSA 125-C:11.