I did replace mine since it was original to the coach. By visual inspection and weight ("full" weight is listed on the unit) it appeared to be fine.
Since we use our genny quite a bit the peace of mind was worth a few hundred bucks.
If memory serves, I replaced it with a Sea Fire FG75A from Pacific Marine and Fire. It wasn't quite a plug and play change since the body diameter of the new one was slightly larger than my old one. Had minor interference with the framework holding the radiator as the genny tray slid in and out.
Fire extinguishers are different, in terms of usage (one time versus rechargeable) and servicing.
Generally, the better Amerex extinguisher can be serviced at 6 years for around $20. This is new seals, agent, and pressure check.
Some of the expensive agents, such as the HFC used in the Sea Fire, is stable enough to it warrant servicing like a dry Chem would; it doesn’t compact. The big concern is that the unit is holding pressure. So, if the gauge is still in the green range, there’s really no risk of the agent and extinguisher being able to discharge its contents.
So, the last component would be to make sure the sprinkler head is clean enough free of obstruction or debris that could delay its activation.
I have not problem with an extinguisher that’s many years old but had retained its pressure and have successfully discharged extinguishers that are as much as 15 years old.
Steve & Janice Vance
2015 Newell #1524
Glendora, CA
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