The Heater,duct Type,stationary, cataloged under National Stock Number 4520-01-541-0657, is classified within Federal Supply Class 4520 (Space and Water Heating Equipment) of the Plumbing, Heating, and Waste Disposal group. The manufacturer of record is Imeco Inc. Government technical data includes 13 specifications, cited from the U.S. Government catalog. The record lists 1 manufacturer part number for this item, enabling identification through both NSN and commercial part number lookups. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog. 1 item shares a part number with this NSN in the catalog (possible match — not a government interchangeability claim). Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 4520-01-541-0657 |
| Primary Part Number | VDHL-18X16-2(417.0-3)-18CBD |
| Item Name | Heater,duct Type,stationary |
| FSC / FSG | 4520 / 45 — Space and Water Heating Equipment |
| Manufacturer | Imeco Inc |
| Status | ACTIVE |
| Phase | THREE |
| Frequency in Hertz | 60.0 |
| Current Type | AC |
| Heat Medium Type | AIR |
| Voltage in Volts | 450.0 |
| Heat Delivery Direction | HORIZONTAL |
| Height | 483.0 MILLIMETERS NOMINAL MM |
| Depth | 368.0 MILLIMETERS NOMINAL MM |
| Width | 746.0 MILLIMETERS NOMINAL MM |
| Circulated Air Type | HEATED |
| Mounting Type | VENTILATION DUCT |
| Heating Element Type | ELECTRIC NONIMMERSION |
| Operating Control Type | THERMOSTATIC |
| Acquisition Status | ACTIVE |
| DEMIL Code | DEMIL A — No Demilitarization Required |
| Hazard | No hazard code in the DLA record (HMIC N) |
| Criticality Code | X |
| Part Number | Manufacturer |
|---|---|
| VDHL-18X16-2(417.0-3)-18CBD PRIMARY | Imeco Inc (USA) |
| Reference | Meaning |
|---|---|
| 24087-512-0506 | D/9 Drawing number reference only Imeco Inc |
NSN 4520-01-541-0657 is a Heater,duct Type,stationary, manufactured by Imeco Inc, classified under FSC 4520, Space and Water Heating Equipment. Status: active.
NSN 4520-01-541-0657 has 1 manufacturer part number on file: VDHL-18X16-2(417.0-3)-18CBD (Imeco Inc).
1 possible match (shared part number, not a government interchangeability claim): 4520-01-541-1537. Verify interchangeability with system specifications before substitution.
Key specifications for VDHL-18X16-2(417.0-3)-18CBD: Phase: THREE; Frequency in Hertz: 60.0; Current Type: AC; Heat Medium Type: AIR. 13 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.