Every maintenance interval counts forward from a single date, and "check the date of manufacture" opens the same step in Amerex manual after Amerex manual. They do not agree on where it is. On a stored-pressure dry chemical portable it is "printed on the extinguisher label (nameplate) or on the agent cylinder dome." On a High Performance dry chemical unit it may be "inside the bottom lip of the cylinder." On a Model 571 Class D copper it is on the wall hanger loop.
Here is the whole schedule in one place: each event, its interval, what restarts the clock, the parts it consumes, and where each family stamps its date.
The five events, in Amerex's own words
| Event | Interval Amerex publishes | What it is |
|---|---|---|
| Inspection | "monthly or more often if circumstances dictate" | A "quick check" that the unit is available and operable |
| Maintenance | "At least once a year or more frequently if circumstances require" | A "thorough check" — examination, repair, replacement |
| Complete maintenance (six year teardown) | Every six years, stored pressure units on 12 year hydro | Emptied, valve disassembled, examined, rebuilt, recharged |
| Hydrostatic test | Every 5 or 12 years by agent — see below | Cylinder proof-tested to the nameplate test pressure |
| Recharge | "IMMEDIATELY AFTER ANY USE" | Refill with the nameplate agent, repressurize, reseal |
Everything past the monthly check is professional work. Amerex's service manuals put it plainly: "When maintenance is indicated, it shall be performed by trained persons having proper equipment." We sell the parts those visits consume, not the service.
The monthly check
Amerex reproduces the NFPA 10 inspection checklist in manual P/N 05602 — seven items covering location, access, gauge reading, fullness, the nameplate facing outward, seals and tamper indicators, and physical damage. It is the only interval on this page a facility can run itself, and it is short enough to do standing in front of the cabinet. We print all seven verbatim, and set out what each failed checklist line resolves to in parts — and the one finding with no part behind it, in the inspection guide.
Annual maintenance is where the other clocks get read
Amerex defines it as a "thorough check" that "includes a thorough examination for physical damage or condition to prevent its operation and any necessary repair or replacement. It will normally reveal if hydrostatic testing or internal maintenance is required."
That last sentence matters. The annual visit is when a technician reads the date of manufacture, weighs the extinguisher and compares it "with weight printed in the 'Maintenance' section on the nameplate (label)," and decides whether a hydro test or teardown is now due.
The six year teardown, and what restarts the clock
From P/N 05602, quoting NFPA 10:
"Every six years, stored pressure extinguishers that require a 12 year hydrostatic test shall be emptied and subjected to the applicable maintenance procedures. When the applicable maintenance procedures are performed during periodic recharging or hydrostatic testing, the six year requirement shall begin from that date."
Two consequences. First, it applies to the 12-year-hydro agents — dry chemical, dry powder, Halotron I, Halon 1211. The Halotron I manual repeats it: "Per NFPA 10 these extinguishers shall be emptied and subject to complete maintenance every six years." For the 5-year agents the wet chemical and water mist manuals instead direct "REPLACE EXTINGUISHING AGENT WITH NEW AMEREX CHARGE AT TIME OF HYDROTEST." Second, the six year clock is resettable. Any recharge or hydro test at which those maintenance procedures were performed becomes the new start date: a unit properly recharged in year four owes its teardown in year ten.
Amerex also notes: "Some states have legislation which requires 'Complete Maintenance' on an annual basis."
One family sits outside all of this. Amerex's catalog states that "HALOTRON® BrX EXTINGUISHERS HAVE A 12-YEAR SERVICE LIFE AND ARE NON-RECHARGEABLE," and manual P/N 27794 excludes them from the six year requirement outright, because they "are not rechargeable and shall be removed from service 12 years from date of manufacture on the UL nameplate." For BrX the date starts a countdown, not a maintenance cycle — the calculation our recharge or replace guide works through.
Hydrostatic intervals, by agent
P/N 27794 states the split in one sentence: five years for water mist, water, wet chemical, foam and carbon dioxide; twelve for dry chemical, dry powder, Halotron I and Halon 1211. Amerex's exact wording, and the CO2 peculiarities that warrant their own article, are in Amerex CO2 Is Different.
Wheeled units run a second clock. On 50 lb models 495, 496 and 497 the agent cylinder is "hydrostatically tested initially at 12 years," then "every 7 years there after if using the proof pressure method or every 12 years there after if using the water jacket method." The 125 and 250 lb High Performance wheeled units read "every 12 years (first time), every 7 years thereafter." On nitrogen cylinder and cartridge operated units the agent cylinder, discharge hose assembly and nitrogen supply hose are all tested at 12 years, and the nitrogen cylinder "must be retested in accordance with DOT regulations" on its own crown-stamped date — on Class D wheeled units, the Argon cylinder, "every 5 years."
Where to find your date of manufacture
Each location below is quoted from that family's own Amerex service manual.
| Family (Amerex manual) | Where Amerex says the date is | Hydro |
|---|---|---|
| Dry chemical portables — ABC, Regular, Purple K (05602) | "printed on the extinguisher label (nameplate) or on the agent cylinder dome" | 12 yr |
| High Performance dry chemical portables, Galvanized & Z-Series (05616) | "printed on the extinguisher label (nameplate) or inside the bottom lip of the cylinder" | 12 yr |
| Halotron I portables, A384T, B385TS, B386T, B394TS, 397, 398 (14425) | "on the extinguisher nameplate" | 12 yr |
| Halon 1211 portables (05604) | "printed on the extinguisher label (nameplate)" | 12 yr |
| CO2 portables, 321M through 332 (05603) | "stamped on the cylinder dome" | 5 yr, per DOT |
| Wet chemical portables, B260/B262, C260/C262 (13259) | "on the extinguisher cylinder hanger loop or on the extinguisher nameplate" | 5 yr |
| Water mist, B270/B272, C270/C272 (16303) | "printed on the extinguisher label (nameplate) or on the agent cylinder dome" | 5 yr |
| Stainless steel water, 240 (05601) | "on the extinguisher cylinder hanger loop or on the extinguisher nameplate" | 5 yr |
| Class D 30 lb, 570 / B570 (08220) | "stamped on the bottom of the extinguisher or nameplate for model B570 and on the wall hanger loop for Model 570" | 12 yr |
| Class D copper, B571/C571 / 571 (05619) | "stamped on the bottom of the extinguisher for Model B571/C571 and on the wall hanger loop for Model 571" | 12 yr |
| 50 lb dry chemical wheeled, 495–497 (05612) | "printed on the extinguisher nameplate or on the agent cylinder dome" | 12 yr, then 7 (proof) or 12 (water jacket) |
| 125 / 150 lb nitrogen cylinder dry chemical (05605) | "printed on the extinguisher label (nameplate) or on the agent cylinder dome" | 12 yr |
| High Performance galvanized wheeled, 573–575 and 690 (05617); Z-Series 756–759 (27085) | "on the extinguisher dome" | 12 yr, then 7 (proof) or 12 (water jacket) |
| Class D wheeled, 680 / 681 (05620) | "on the extinguisher nameplate or on the agent cylinder dome" | 12 yr |
The nameplate is a listed location for almost every family, which is why an illegible one is not cosmetic: it is the record the schedule is read from, and where the test pressure appears.
What each event consumes
The annual visit takes small items: a tamper seal ("Install new tamper seal if broken"), a ring pin "if bent or if removal appears difficult," a gauge if "bent, damaged or improper."
The teardown takes more, because the valve comes apart. Amerex's step 10 is explicit: "Remove and disassemble valve assembly by removing downtube, spring and valve stem assembly. Install a new valve stem and collar O-ring after lightly lubricating with Visilox V-711." A new stem and collar O-ring are not optional at that interval; the collar O-ring, valve stem, spring and downtube assembly are inspected and replaced "if worn or damaged," and the unit takes a full agent refill.
Which stem and O-ring depends on whether the valve is aluminum or brass, a split that runs through hanger loops too — our aluminum vs. brass valve guide covers it. Gauges take one step more: pressure rating decides alongside valve material, so the 240 psi 05225-P belongs to the 6 kg to 30 lb High Performance and Z-Series units and the 195 psi 27603-P to the 30 lb Class D units, though all of those lists run a brass valve. Our gauge cross-reference sets out which gauge each parts list calls for. On sourcing Amerex is unambiguous: "Only factory replacement parts are approved for use on Amerex fire extinguishers." Of the substitutes, "None of these meet UL requirements and all of them void the Amerex extinguisher warranty and UL listing. DO NOT SUBSTITUTE."
When the nameplate itself is the failed part
Faded and painted-over nameplates are common outdoors and in wash-down areas. Amerex's first maintenance step is to "check to make sure that the instruction nameplate is securely attached and legible," and the owner's manual asks at every inspection that "the operating instructions are clearly visible." We stock Amerex replacement nameplates, with one caveat the Parts Book prints in two wordings. On the 6 kg–30 lb High Performance and Z-Series list it reads "** Nameplates do not include UL and USCG Listing." On the wheeled and other lists it reads "* Nameplates do not include UL or USCG" — eight lists carry that second version. Either way the meaning is the same: a replacement restores the operating instructions and maintenance data, not the listing marks. Where the listing is itself a compliance requirement — a marine installation being the clearest case, since a Coast Guard approval is read off the nameplate — ask your service company and your AHJ before the old plate comes off.
What we stock
Teardown valve internals — 06092 aluminum and 06093 brass valve stem assemblies with the matching 05241 and 05240 collar O-rings, plus downtube and retainer assemblies by cylinder size — the 01700 is the Parts Book's 6 kg (13.2 lb) High Performance and Z-Series listing.
Annual-visit consumables — 01387 yellow lock wire seals, 00160 stainless ring pins, and gauges by pressure rating as well as valve platform — 03103 aluminum and 03965 brass at 195 psi, 05225 at 240 psi for the 6 kg to 30 lb High Performance and Z-Series units, 27603 at 195 psi for 30 lb Class D. Full range in valves, gauges and downtubes and O-rings, seals and pull pins.
Agent, labels and hanger loops — charge 550 ABC dry chemical in the 50 lb pail and the rest of the recharge agents; nameplates such as the 23506 (High Performance ABC 564 and 581), among 45 nameplates, labels and decals; and hanger loops by family — 14380 for foam, water mist and wet chemical, 17144 for Class D, 14220 for aluminum valve units.
Working out what a mixed-age fleet needs at its next interval? Send model numbers and dates of manufacture and we'll come back with a parts list and lead time — request a quote.
Sources
Everything above is quoted from Amerex Corporation's owner's service manuals P/N 05601, 05602, 05603, 05604, 05605, 05612, 05614, 05616, 05617, 05619, 05620, 08220, 13259, 14425, 16303, 27085 and 27794, the Amerex Parts Book, and Amerex's portable fire extinguisher catalog. Confirm every interval and test pressure against your own extinguisher's nameplate, and your obligations with a qualified fire protection professional and your AHJ — some states impose stricter schedules than NFPA 10.
ShopAmerex.com is owned and operated by Centurion Holdings Group LLC, an independent authorized distributor of Amerex Corporation products. We sell equipment and factory OEM service parts — we do not perform inspection, service, hydrostatic testing or recharging.