scope:

PREFACE

The standards set forth herein apply to the seventh edition of the Standard for Gas-Fired Gravity and Fan Type Direct Vent Wall Furnaces, ANSI Z21.44-1985, and Addenda thereto, Z21.44a-1985, and supersede corresponding standards therein. Following their preparation by the supervising subcommittee, they were accepted by Accredited Standards Committee Z21 and subsequently approved as American National Standard by the American National Standards Institure, Inc.

NOTE: Changes, other than editorial, are denoted by a vertical line in the margin.