fire extinguisher for engine room

[LittleSister]

other methods like Water Mist, Foam or Powder require directional accuracy.

As I posted above, the instructions for my powder automatic extinguisher didn't suggest any requirement for directional accuracy.

I'm planning on a cheap 3kg CO2, with a remote pull handle release.

Will 3kg CO2 be sufficient for the volume of your engine compartment and bilges?

 

[rszemeti]

As I posted above, the instructions for my powder automatic extinguisher didn't suggest any requirement for directional accuracy.

Shrug ... good luck with that one then. When all the powder is in the bilge, and the top of the engine is still on fire, please feel free to contact the manufacturers to discuss the accuracy of their leaflet. Dry Powder extinguishers work by forming a barrier between the fire and the source of oxygen, in other words you have to smother the fire with the powder for it to work. If the powder is being discharged on one side of the engine and the fire is on the other side, or in a difficult to reach place, it won't have any effect.

Will 3kg CO2 be sufficient for the volume of your engine compartment and bilges?

Plenty. Using the reference value of 1.96 g/litre for CO2 at STP, a 3kg CO2 cylinder will expand to a volume of around 6 m^3 which is more than enough to flood my engine compartment and bilges. I am confident that it will remove the oxygen from an oil or fuel fire ... no matter where in the engine compartment it is. The down side is of course, they do not cool the fire, so there is a potential for re-ignition, it is often recommended to back a CO2 up with a manual foam extinguisher.

 

[geem]

Have you considered a remote activated CO2 or watermist fire extinguisher together with a smoke detector so you know when a fire has started and can shut down the engine before setting off the fire extinguisher

The great thing about water mist is you dont need to shut down the engine. It will have no ill effect on engine performance but might actually improve it. We did plenty of tests and research on data centre standby generators and high pressure watermist. We couldn't afford to lose the generators in a fire so chose watermist as the extinguishing system. Water mist is installed on mega yachts for this reason.

 

[FlyingGoose]

Might be a daft question , but would water mist on a hot engine maybe potentially crack the casing or other metal parts of the engine