TM 5-4520-256-24P CO1
5. SPECIAL INFORMATION.
a. USABLE ON CODE. The usable on code appears in the lower left comer of the Description column
heading. Usable on codes are shown as UOC:..... in the Description Column (justified left) on the last line
applicabie item description/nomenclature. Uncoded items are applicable to all models. Identification of the
usable codes used in this publication are:
Air Force Model H82
Army Model H83
b. ASSOCIATED PUBLICATIONS. The publication listed below pertains to the Portable Duct Heater
and its components.
Heater, Duct Type, Portable, HDU-36E,
120,000 BTU, Models H82 and H83
6. HOW TO LOCATE REPAIR PARTS.
a. When National Stock Number of Part Number is NOT Known.
Using the table of contents, determine the assembly group or subassembly group to which
the item belongs. This is necessary since figures are prepared for assembly groups and subassem-
bly groups, and listings are divided into the same groups.
(2) Second. Find the figure covering the assembly group or subassembly group to which the item
Identify the item on the figure and note the item number.
Refer to the Repair Parts List for the figure to find the part number for the item number
noted on the figure.
Refer to the Part Number Index to find the NSN, if assigned.
b. When National Stock Number of Part Number is Known:
Using the Index of National Stock Numbers and Part Numbers, find the pertinent National
Stock Number or Part Number. The NSN index is in National Item Identification Number (NIIN)
sequence (see 4A(l)). The part numbers in the Part Number index are listed in ascending alphanu-
meric sequence (see paragraph 4b). Both indexes cross-reference you to the illustration figure and
item number of the item you are looking for.
After finding the figure and item number, verify that the item is the one you are looking
for, then locate the item number in the repair parts list for the figure.
7. ABBREVIATIONS. Abbreviations used in this manual are listed in MIL-STD- 12.