The Valve,relief,pressure and Temper, cataloged under National Stock Number 4820-00-761-1981, is classified within Federal Supply Class 4820 (Valves, Nonpowered) of the Valves group. The manufacturer of record is The Electric Heater Co Dba Hubbell Electric Heater Co.. Government technical data includes 19 specifications, cited from the U.S. Government catalog. The record lists 3 manufacturer part numbers 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through both NSN and commercial part number lookups. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog. 3 items share a part number with this NSN in the catalog (possible match — not a government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 | 4820-00-761-1981 |
| Primary Part Number | HSRV-1-85 |
| Item Name | Valve,relief,pressure and Temper |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Manufacturer | The Electric Heater Co Dba Hubbell Electric Heater Co. |
| Status | ACTIVE |
| Flow Control Device | POPPET |
| Temp Rating | 180.0 FAHRENHEIT DEGF |
| Second End Relationship with First End | NOT IDENTICAL |
| Body Style | ANGLE GIVE "ADQM" AND "ADQN" ONLY IF FLANGED ONE OR TWO ENDS |
| First End Style Designator | PLAIN |
| Second End Nominal Pipe Size Accommodated | 0.250 INCHES IN |
| End Connection Quantity | 2 |
| Second End Style Designator | PLAIN |
| Opening Pressure Setting | ERR-060 |
| Temp Control Device Type | FUSIBLE |
| First End Connection Type | UNTHREADED INTERNAL PIPE |
| Temp Adjustability | NOT ADJUSTABLE |
| First End Nominal Pipe Size Accommodated | 0.500 INCHES IN |
| Material | COPPER ALLOY BODY |
| Material | COPPER ALLOY FLOW CONTROL DEVICE |
| Material | STEEL CORROSION RESISTING STEM |
| Material | COPPER ALLOY SEAT |
| Media for Which Designed | WATER, FRESH |
| Second End Connection Type | UNTHREADED INTERNAL PIPE |
| 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 |
|---|---|
| 1771093 | The Electric Heater Co Dba Hubbell Electric Heater Co. (USA) |
| HSRV-1-85 PRIMARY | The Electric Heater Co Dba Hubbell Electric Heater Co. (USA) |
| HSRV-1 PRIMARY | The Electric Heater Co Dba Hubbell Electric Heater Co. (USA) |
| Reference | Meaning |
|---|---|
| 17723-7 | 5/9 Secondary reference The Electric Heater Co Dba Hubbell Electric Heater Co. |
NSN 4820-00-761-1981 is a Valve,relief,pressure and Temper, manufactured by The Electric Heater Co Dba Hubbell Electric Heater Co., classified under FSC 4820, Valves, Nonpowered. Status: active.
NSN 4820-00-761-1981 has 3 manufacturer part numbers on file: 1771093 (The Electric Heater Co Dba Hubbell Electric Heater Co.), HSRV-1-85 (The Electric Heater Co Dba Hubbell Electric Heater Co.), HSRV-1 (The Electric Heater Co Dba Hubbell Electric Heater Co.).
3 possible matches (shared part number, not a government interchangeability claim): 6750-01-427-1858, 4820-01-509-9498, 4820-01-523-7082. Verify interchangeability with system specifications before substitution.
Key specifications for HSRV-1-85: Flow Control Device: POPPET; Temp Rating: 180.0 FAHRENHEIT DEGF; Second End Relationship with First End: NOT IDENTICAL; Body Style: ANGLE GIVE "ADQM" AND "ADQN" ONLY IF FLANGED ONE OR TWO ENDS. 19 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.