Gents, I have always intended to install a sprinkler in the engine compartment and feed it water from freshwater holding. My thought was to activate it with a "high temp" mechanical sensor and a manual valve. I know that water won't put out an electrical fire and it will only get diesel and hydraulic fluid to below their flash point. The upgrade stage I thought about was a chemical tank that added a flame suppressor to the water before it get sprayed. I read about this many years ago and the article was about aircaft fire fighting. Seems the trucks have two tanks aboard and mix the stuff as needed. Problem back then was chemical expense and cleanup. Delivery was dirt simple. Anybody know how this system has evolved and what the costs/technology is? I know that I am way out of my deapth here but if I were watering my lawn and a bus puled up and flames came out of the engine compartment, well the thing would get quickly as wet as I could make it and I don't think I stand out on this. Having fun.
JohnEd:-\
OK, this is just off the top of my head and probably will be shot down easily by the experts, but lets try it:
1.) An acummulator tank, such as is used for household well pumps. Maybe about 2-5 gallons depending on space and needs.
2.) Remove the schraeder valve and hard connect an airline from the primary air tank with a pressure regulator set to around 80-100 lbs.
3.) On the output side, fill the thing with about 10-16 oz. of baking soda.
4.) Install an electrically operated solenoid that allows only one way travel of the contents: Outward.
5.) Between the solenoid and the accumulator, install a 40lb tank of argon. (about $150 for the refillable tank plus the argon. $20 to refill. {It can also be used for welding aluminum in TIG and MIG welding}, Throw away tanks may be less, but I don't know where to find them. Besides, I'm not sure how much argon you would need for the typical engine fire). Also install a pressure regulator limiting pressure to 120 lbs.
6.) Downstream from the accumulator, install a small tank of vineagar using a small tube 1/2 the size of the 3/8" copper tubing you are using to deliver the pressurized bicarbonate of soda. Something like the draw from a pressure washer that delivers the detergent.(Pitot?)
7.) In the engine bay, mount 6 spray nozzles, available from plumbing shop or Big Box store, connected with copper or stainless tubing to the output of your accumulator and vineager setup.
8.) connected to your check/valve solenoid on the accumulator tank, wire in the thingy that turns a coffee pot or electric frying pan off when it reaches over 220°
9.) As long as the temp is below 220° the solenoid will not energize. once energized, the system will throw out baking soda and mix it with vineagar, making a foam. The foam is useable on fuel and electrical fires as soon as the vineager vaporizes, which shouldn't take long.
10.) You will have to find the best place to put the heat sensor to keep it from going off prematurely, or, go to Radio Shack® and find a higher value for your actuator.
This system should cost well less than $200 and if you can find the throwaway Argon tanks, less than $100.
Now, Someone, PLEASE tell me how this can't work.
Dallas
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