The Heater,ventilation,duct Type, cataloged under National Stock Number 4520-00-271-9753, is classified within Federal Supply Class 4520 (Space and Water Heating Equipment) of the Plumbing, Heating, and Waste Disposal group. Government technical data includes 14 specifications, cited from the U.S. Government catalog. 4 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. 3 items share a part number with this NSN in the catalog (possible match — not a government interchangeability claim). Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 4520-00-271-9753 |
| Item Name | Heater,ventilation,duct Type |
| FSC / FSG | 4520 / 45 — Space and Water Heating Equipment |
| Status | ACTIVE |
| Heat Medium Type | HOT WATER OR STEAM |
| Duct Height | 14.000 INCHES IN |
| Heat Outlet Quantity | 1 |
| Duct Width | 3.250 INCHES IN |
| Heat Discharge Outlet Type | STATIONARY |
| Heat Delivery Direction | HORIZONTAL |
| Height | 20.750 INCHES NOMINAL IN |
| Surface Treatment | ZINC |
| Maximum Pressure Limit | 300.0 POUNDS PER SQUARE INCH GAGE LBS |
| Depth | 5.000 INCHES NOMINAL IN |
| Width | 6.250 INCHES NOMINAL IN |
| Heat Directing Device | RADIAL DIFFUSER-VERTICAL VANES |
| Mounting Type | VENTILATION DUCT |
| Heating Element Type | HOT WATER COIL OR STEAM COIL |
| Acquisition Status | ACTIVE |
| DEMIL Code | DEMIL A — No Demilitarization Required |
| Hazard | No hazard code in the DLA record (HMIC N) |
| Criticality Code | X |
| Reference | Meaning |
|---|---|
| S3802-66970 | D/9 Drawing number reference only U.S. Government activity |
| S23MNM | 3/1 Design control — primary reference U.S. Government activity |
| S3802-66970S23MNM | 3/1 Design control — primary reference U.S. Government activity |
| MIL-H-16235 | 4/1 Identification reference U.S. Government activity |
NSN 4520-00-271-9753 is a Heater,ventilation,duct Type, classified under FSC 4520, Space and Water Heating Equipment. Status: active.
3 possible matches (shared part number, not a government interchangeability claim): 4520-00-273-1058, 4520-00-273-1257, 4520-00-273-1277. Verify interchangeability with system specifications before substitution.
Key specifications for 4520-00-271-9753: Heat Medium Type: HOT WATER OR STEAM; Duct Height: 14.000 INCHES IN; Heat Outlet Quantity: 1; Duct Width: 3.250 INCHES IN. 14 specifications are documented in the U.S. Government catalog.
No hazard code in the DLA record (HMIC N). Hazard information on this page is shown exactly as it appears in the DLA record.
U.S. Government catalog: edition PUBLOGDVD v12.0.0 (OCT 2026), edition date 2026-10-01, retrieved 2026-10-16.
U.S. Government catalog: edition PUBLOGDVD v12.0.0 (OCT 2026), edition date 2026-10-01, retrieved 2026-10-18.