I don't know about the age factor - mine was only about 3 years old. It got bumped by a tire that was kinda rolling around a bit back there. They aren't supposed to go off without the pin being pulled first, but that wasn't the case with mine. The handle must have got pushed (bumped) and somehow the pin flew out and it was ON until it emptied! yuck

Anyway, I'm gonna tackle the cleaning project tomorrow if it's not pouring rain.

Does anyone have brands that don't get set off with the pin is still in it? I thought that was supposed to be a safety feature. Hmm, not so much...

 

Oh ok, so maybe the pin fell out. The little plastic tie that keeps the pin in place often gets brittle and breaks after a few years. Mine now has a wire twist tie holding the pin in place because I noticed my pin about to fall out a few years ago.

 

That is the reason the good ones cost more, cause they are good

But a unit from a fire extinguisher shop rather than Lowes or Home Depot. It will last longer, work better and it won't "go off" for no reason. Temp and age have almost nothing to do with it. They are charged with Nitrogen so it is largely unaffected by temp. As long as the bottle is not corroded and the valve is decent (metal, not plastic) it should last forever.

Lamm

 

Multi-Purpose Dry Chemical (A, B, C)
A dry chemical agent called mono ammonium phosphate. The chemical is non-conductive and can be mildly corrosive if moisture is present.

See this thread Mounted a fire extinguisher

 

A dry chemical extinguisher is perfectly harmless. If it comes out white then it is only sodium bicarbonate (baking soda). If the powder is purple then I believe it is Potassium Bicarbonate or similar (known as Purple-K). Both are in B-C extinguishers only. The A-B-C extinguishers I believe are monoammonium phosphate (yellow colour). All are non toxic. In fact the only way that they are in anyway bad for you is the temporary respiratory problems from just having inhaled a powder. Might not be the best if you have asthma or something but other then that it can't hurt you. The only real toxic extinguishers are the Halon variety which are quite toxic and bad to inhale. Dry chem will mess up anything electronic in a hurry so watch were you spray it.

Age should have nothing to due with it going off unless it was damaged some how. As was mentioned it is simply a bunch of powder and pressurized Nitrogen which isn't affected by temp. As long as you give the extinguisher a shake every now and then so that the powder doesn't 'cake' in the bottom the extinguisher should pretty much last forever unless it is damaged or the Nitrogen leaks out somehow. If yours went off with the pin in it then my guess is that it is a cheap POS. I would buy a better one. I would say that 10lbs is about the minimum that you should carry.

C02 would be another good choice for a vehicle. It is only B-C rated but that usually doesn't matter in a vehicle fire. Halon is what is normally used for vehicles but it is nasty stuff. CO2 is safer and also has the benefit of being able to cool off beer in a hurry as well as not make a mess or damage your interior. I will be adding a C02 extinguisher to my truck to as a primary extinguisher to supplement the Dry Chem that I a already have.

 

Thanks to everyone for all the great information! The truck has pretty much been cleaned up, so now I'm in research mode for a replacement extinguisher. :fireman:

 

Update story!

It never fails - when you need an extinguisher, you don't have one! This is the 3rd time it's happened to me.

I haven't purchased a replacement yet, and guess what happened today? Yep, a lady comes running over to me asking if I had an extinguisher because her minivan engine was on fire. I felt so bad and so guilty!