ShopAmerex.com · Amerex 06789 datasheet · https://shopamerex.com/products/amerex-06789-nitrogen-tube-assembly-300 · Figures as published by Amerex · Verified Sep 2, 2026
Genuine Amerex service part·Part no. 06789
Amerex 06789 Nitrogen Tube Assembly 300
Amerex 06789 is the nitrogen tube assembly listed as item 6 in Amerex Parts Book 27277 Rev D, printed page 19, for the 300/350 lb nitrogen-cylinder wheeled extinguishers, models 491 and 493. Full overview ↓
- Part no.
- 06789
- Pack
- Each
- Parts Book
- Page 21
- Free shipping (orders over $100)
- Returns per our refund policy.
Genuine Amerex part from an authorized Amerex distributor. Not a generic substitute.
Ordering parts for a service route?
Quotes for part lists, PO and tax-exempt orders, and parts not yet listed.
Which models does the Amerex 06789 fit?
Per the Amerex Parts Book · page 21| Fits | Extinguisher | UL rating | Capacity | Price | Link |
|---|---|---|---|---|---|
| Model 491 |  11677 Amerex 491 300 lb Wheeled ABC Fire ExtinguisherParts Book p.19 |
40A:320B:C | 300 lb (136.07 kg) | $9,515.00 | View |
| Model 491R |  11604 Amerex 491R 300 lb Wheeled ABC Fire Extinguisher with Rubber Tread WheelsR variant of 491 |
40A:320B:C | 300 lb (136.07 kg) | $8,981.00 | View |
| Model 493 |  15505 Amerex 493 300 lb Wheeled Purple K Fire ExtinguisherParts Book p.19 |
320B:C | 300 lb (136.07 kg) | $9,413.00 | View |
| Model 493R |  17944 Amerex 493R 300 lb Wheeled Purple K Fire ExtinguisherR variant of 493 |
320B:C | 300 lb (136.07 kg) | $10,511.00 | View |
Parts list for 300/350 lb. dry chemical wheeled models, 55 cu. ft. nitrogen cylinder
Fitment per the Amerex Parts Book. Check the part number against your unit’s nameplate before ordering.
What is the Amerex 06789?
Amerex 06789 is the nitrogen tube assembly listed as item 6 in Amerex Parts Book 27277 Rev D, printed page 19, for the 300/350 lb nitrogen-cylinder wheeled extinguishers, models 491 and 493. The Parts Book places it in the agent cylinder cap group, between the nitrogen hose assembly (item 5) that runs to the 55 cu. ft. nitrogen cylinder valve and the downtube assembly (item 7). Amerex states that its replacement parts must be used to protect the UL listing and to keep the warranty in effect, and warns that failure to use Amerex replacement parts could cause the extinguisher to malfunction. Service is covered by Owner's Service Manual PN 05614.
Amerex 06789 specifications
| Part number | 06789 |
|---|---|
| Description | Nitrogen Tube Assembly |
| Parts Book page | printed page 19 (PDF page 21) |
| Diagram item | 6 |
| Models | 491, 493 |
|---|
| Amerex item number | 06789 |
|---|
Part data as published by Amerex. Confirm against the current Parts Book revision before ordering for a unit in service.
Amerex 06789 documents
Official Amerex publications · PDFCurrent Amerex publications, hosted on ShopAmerex so links do not break when Amerex reorganizes its site.
Other parts on Parts Book page 21
Parts list for 300/350 lb. dry chemical wheeled models, 55 cu. ft. nitrogen cylinder · All 12 parts| Part no. | Part | Pack | Price | Quantity and add to cart |
|---|---|---|---|---|
| 06809 | Each | $1,452.00 | ||
| 06814 | Each | $921.00 | ||
| 07026 | Each | $1,324.00 | ||
| 07292 | Each | $135.00 | ||
| 07607 | Each | $1,882.00 | ||
| 08260 | Each | $102.00 | ||
| 08261 | Each | $132.00 | ||
| 17235 | Each | $260.00 |
Item numbers refer to the exploded view on the Parts Book page. Model-specific items are marked in the Amerex parts list; confirm before ordering.
Amerex 06789 questions
What does the Amerex 06789 nitrogen tube assembly fit?
Amerex 300/350 lb wheeled models 491 (ABC) and 493 (Purple K), including the 491R and 493R variants.
Is the Amerex 06789 a genuine Amerex part?
Yes — it is the factory nitrogen tube assembly listed in the Amerex Parts Book, not a substitute.
Where is the 06789 listed in the Parts Book?
Item 6 on printed page 19 (PDF page 21), between the nitrogen hose assembly (item 5) and the downtube assembly (item 7).
What is this part's role in the extinguisher?
The Parts Book places it in the agent cylinder cap group next to the nitrogen hose that runs to the nitrogen cylinder valve. Amerex does not publish a functional description beyond the part name and that diagram position.
What happens if a substitute part is used?
Amerex states that Amerex replacement parts must be used to protect the UL listing and keep the warranty in effect, and that failure to use them could cause the extinguisher to malfunction.
Which service manual covers the extinguishers this part fits?
Amerex Owner's Service Manual PN 05614, covering wheeled models 491, 492 and 493.
Can the Amerex 06789 be used on other Amerex models?
No — 06789 appears only once in Parts Book 27277 Rev D, on the 491/493 parts list.