Automatic Fire Suppression for Diesels?

As we are Very close to purchasing our boat, the list of 'Must Haves' is being weighed out. We believe it would give a little more Peace of Mind to have a Halon or other system in this engine room, but wanted to put it out to the Forum to help gather a little more information. I have heard that a Diesel will continue to RUN on Halon, and that an electrical solenoid must be put in line to Shut Off air intake, should the system be activated. Would anyone with first hand knowledge please chime in. The system would be for a 43' with twins.

Our Surveyor mentioned at least putting in a small access port to the engine room, where a Large Hand Held Extinguisher could be used - without having to open a larger hatch - thus letting in more Air for a fire.

Thanks,
Tamara & Kim

I guess my question would be why? There is a difference between a runaway diesel which cutting off the air or fuel supply is the only way to stop it. Or fire suppression in the engine room which is what Halon is for. The normal engine shut off has as much chance of working as an electric solenoid used to shut off air to the engine in case of fire.

In a recent thread on the same topic on the sister site, there was concern that a running engine might ingest and exhaust the halon before it could extinguish the fire. So, a sequence:

1. Alarm
2. Shut down engine, exhaust fan and fuel supply.
3. Halon (or its successor), to snuff the flames, quickly followed by
4. Water, to cool things off.

That other thread is worth a read. A cruiser lost their boat to an engine room fire. Scary how quickly things went wrong for them. They had to get off the boat before they could don pfds or launch the dink. They were lucky to be picked up by a passing boat.

A runaway diesel dose not need any diesel to run. Cutting off the diesel supply dose not do anything. You need to starve the engine of oxygen.

A runaway diesel is running off the oil that is in the engine. from the way i understand it most of the time it happens when the rings are worn out and the oil gets into the cylinders.

In the 90's i was on driving a 6 cylinder tractor and had a runaway. A 5 pound ABC extinguisher in the air intake slowed it down, but not for long.

choppywater said:

A runaway diesel dose not need any diesel to run. Cutting off the diesel supply dose not do anything. You need to starve the engine of oxygen.

A runaway diesel is running off the oil that is in the engine. from the way i understand it most of the time it happens when the rings are worn out and the oil gets into the cylinders.

In the 90's i was on driving a 6 cylinder tractor and had a runaway. A 5 pound ABC extinguisher in the air intake slowed it down, but not for long.

Click to expand...

A runaway can be caused by multiple thing not just oil. an injector stuck at fuel rack, injection pump, ect. also they will run away on gas vapors(anything combustible) if there is enough present.

shutting off all the air entering the engine is the only sure way to stop it. and its best done with an engine mounted air shutoff.

I have seen a few marine engine rooms with Fireboy Halon systems installed, including my boat. AFAIK, it is SOP to set up the system so that the engine stops when the Fireboy is triggered. Probably the main reason is to keep the diesel from ingesting the Halon and exhausting it, thereby keeping it from doing its job.


Can a diesel engine run on Halon in the absence of diesel, if the Fireboy system has triggered the stop solenoid? I really doubt that. That is why Halon, or modern day equivalents are used- it puts out fires by depriving them of oxygen. It doesn't burn itself.


How reliable are the Fireboy engine shutdown systems? Well, I suppose the Cummins type of energize to run is more reliable than the Yanmar type of energize to stop. No matter how the Cummins type loses its electrical energization- an electrical failure due to the fire or the Fireboy doing it, the engine will stop. But I will be that the difference is not material.


So, hook up your Fireboy to the engine stop system.


David

I see the runaway engine and engine room fire are two different concerns and while a runaway engine could potentially cause a fire, the engine room fire is a more likely scenario and the bigger concern. CG inspected passenger vessels are required to have means to block the engine room air intakes, not just turning off a fan but an actual mechanical way to block air flow. Once you cut off the air supply, then you set off the halon system if it hasn't gone off on it's own. Otherwise your engine is sucking fresh air into the engine room and reducing the effectiveness of the halon system. The engine room fire suppression system is critical for electrical fires which from my unscientific research are far more likely to cause a vessel fire than a fuel leak or engine failure. Detriot diesels are particularly susceptible to running away due to the oil seals in their blowers and every marine one I have been around has a mechanical flap to block off air supply should they runaway.

If you are unlucky enough to have a runaway engine at the same time as an engine room fire, your number is up and accept your fate with as much grace as possible.

I once thought that Halon could provide the "fuel" for an engine runaway and that was one of the reasons the Fireboy system shut the engine down before expelling the extinguishing agent. I was told on here that was not the case. I then did my own research and found out that, in fact, a diesel engine will NOT runaway on Halon.

So if the OP was alluding to the fact that Halon can cause a runaway, like I had once thought, I do not believe that to be the case.

I posted the manuals for both the Fire-Boy Xintex and Sea-Fire systems in the Library section - noticed the mods haven't approved them yet.
If anyone is interested let me know and I can post them or send them to you.

I'm not an expert but believe Halon is no longer used in most cases - there are other similar "clean" agents that have replaced Halon and some are even acceptable for occupied space (which I don't think Halon is).

There are manual systems but not sure if/ how they shut down the diesels which is necessary for effectiveness. The auto options have a control box that you can hook up many accessories to auto shut down e.g. ER Blower, alternator, Gen, etc

The Sea-Fire Website & Fire-Boy Website has some useful info about their systems.

If you simply install a small hatch / port how do you ensure someone doesn't use an extinguishing agent that shouldn't be ingested into an engine?

A useful Intro to Fire Extinguishers from West Marine Advisor

This one includes mention of the "Fire Port" To me a consideration would be the need to have a "clean" agent extinguisher available of sufficient size to handle the ER volume - so you need the major component of the auto system and need to find a place to store it near the port - why not just put the auto / remote manual system in the ER??

Another good Cruising World article w/ intro & +/- which includes the following...

"More problematic is this situation: To comply with the latest version of (ABYC) A-4, which went into effect on July 31, 2009, all diesel engines, both propulsion and generators, as well as engine-room blowers must shut down automatically in the event of an extinguisher discharge. Many boats out in the field don't comply with this standard, creating a very dangerous situation. This shutdown requirement is extremely important if the system is to do its job. Diesel engines consume large volumes of air when running and can easily consume your fire-extinguishing agent. Blower systems used to supply air or cool down engine-room spaces can also suck the agent out of the space. The bottom line here should be obvious: Your engine-room fire won't be extinguished."


My vote would be to install a system and sleep well knowing you have protection.

You've Hit on what I heard. In the event the engines were running, as part of the Halon System(or Successor), that the Oxygen to the Engine must be Shut Down automatically or the Air Intake will Use the Halon, like Air - and subsequently Use THAT what was intended to fight the fire. I called a Company in Ft. Myers that was a Distributor for a Suppression product, and was told they will only Service an existing system - not install - for they don't wish to get involved in the Electrical Work required for a Diesel Application. So when I find a company that will do the Whole Enchilada - it will Cost me $$$$.

More than you might want to know about Halon: What is Halon? How does Halon Work? Is Halon legal? Is Halon Safe?

A surprising factoid in the above article is that the FAA likes it for aircraft since it won't poison passengers. I had once learned that firefighters don't like it because the Halon displaces the air in a closed space, making it tough on firefighters. Another surprise is that it has not been made since 1994, systems are sold and serviced using recycled stocks.

Ransom said:

I called a Company in Ft. Myers that was a Distributor for a Suppression product, and was told they will only Service an existing system - not install - for they don't wish to get involved in the Electrical Work required for a Diesel Application.
So when I find a company that will do the Whole Enchilada - it will Cost me $$$$.

Click to expand...

If I was in the market for a system install I'd start w/ contacting Fire-Boy and Sea-Fire to inquire about installers of their products.

I thought it was SOP to install auto engine shutdown with an automatic ER fire suppression system? According to Fireboy, HFC-227ea fire suppressant will not stall a diesel engine and the engine could evacuate the suppressant too fast to put out the fire. Until I bought my current boat I didn't know anything about these new systems but my current boat was upgraded with a Fireboy system by the PO and if triggered it will automatically energize the engine stop solenoids. There is also an override at the lower steering station in case the external situation requires engines.

Automatic Marine Engine Shutdown Systems - Fireboy Xintex


Ken

Strangely, it was a FireBoy Distributor, as listed on FireBoy's Website, that did not wish to do a Full Install.

Ken? Do you remember the Approximate Cost of installing a FireBoy System?

Ransom said:

Strangely, it was a FireBoy distributor as listed on FireBoy's Website, that did not wish to do a Full Install.

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Exactly...many are simply "distributors" Fireboy should be able to steer you to an installer.

Similarly not all distributors of products are approved "service" providers.

The engine must STOP, the ER blowers must STOP , and hopefully their vents closed before the extinguisher is fired.

***

"A surprising factoid in the above article is that the FAA likes it for aircraft since it won't poison passengers."

The airlines hate powered unit as many cockpit switches , circuit breakers and steam gauges need to be replaced , a million bucks worth of effort.

Fire Safety

Ransom said:

As we are Very close to purchasing our boat, the list of 'Must Haves' is being weighed out. We believe it would give a little more Peace of Mind to have a Halon or other system in this engine room, but wanted to put it out to the Forum to help gather a little more information. I have heard that a Diesel will continue to RUN on Halon, and that an electrical solenoid must be put in line to Shut Off air intake, should the system be activated. Would anyone with first hand knowledge please chime in. The system would be for a 43' with twins.

Our Surveyor mentioned at least putting in a small access port to the engine room, where a Large Hand Held Extinguisher could be used - without having to open a larger hatch - thus letting in more Air for a fire.

Thanks,
Tamara & Kim

Click to expand...

The problem with these automatic systems is that they are expensive, but even worse, they don't activate until you have a well developed fire and probably a lot of damage. I had a friend that lost a 52 ft Westport due to a late detected engine room fire. He didn't have a suppression system, but probably could have handled with a hand held portable fire extinguisher if he had caught it in time.

There is an INEXPENSIVE solution to this problem. Both Kidde and First Alert make battery operated SMOKE DETECTORS the are very sensitive and will detect an incipient fire long before an automatic system would activate. The problem of not hearing one located in engine room is easily solved by installing additional wireless linked units at or near helm and on especially on flybridge. The ones that can be linked wirelessly are available at Lowes and Home Depot for about $25-28 each. If the one in the engine room (or any other area) activates, the others will all sound the alarm within a second or two.

That along with a decent size (10 - 15 lb) multi-purpose ABC portable extinguisher is an effective system. Also be sure your VHF radio is accessible at fly bridge, is DSC capable, and you have obtained and programmed your MMSI number into the radio. You can obtain your MMSI number free at BoatUS.com. If your alarm goes off, and you confirm its not a false alarm (like cooking bacon in galley if one of your units is in an area where this happens), 1st thing is hit the orange button on your radio unti it activates then "Rescue 21" system, order your passengers to don their life jackets, answer the Coast Guard on your radio when they respond to the automatic distress call you initiated, then put your attention on safely extinguishing the fire.

For those of you who follow Steve D'Antonio, he just posted a good article concerning fire extinguishers.

I have three. A self releasing halon positioned over each main engine, a CO2 self releasing and a second CO2 manual release. The boat was licensed for 50 day passengers before I bought it. Way more than needed but happy to get it.
I've been to 3 USN firefighting schools. The trick is early notification and quick action on your part. Fires usually start small and smoke and smolder for some time before flashing. A sensor that senses fumes, not just smoke or heat is a better defense. You may stop a fire before it starts.
A runaway diesel is very rare, most engineers never see one. Engines in good repair. receiving proper maintenance don't runaway. The best stop is a method that slowly stops the air flow. A very quick air stop can cause the engine to suck in seals and gaskets. From others experiences I prefer rags in the intake. They don't go far and are easy to clean out. I've only seen 1 runaway 60 years ago on a very big marine diesel. I was a boy watching my dad, a chief engineer evaluating the engine for a ship owner to determine if it could go longer before overhaul. Turned out it couldn't.

djmarchand said:

I have seen a few marine engine rooms with Fireboy Halon systems installed, including my boat. AFAIK, it is SOP to set up the system so that the engine stops when the Fireboy is triggered. Probably the main reason is to keep the diesel from ingesting the Halon and exhausting it, thereby keeping it from doing its job.


Can a diesel engine run on Halon in the absence of diesel, if the Fireboy system has triggered the stop solenoid? I really doubt that. That is why Halon, or modern day equivalents are used- it puts out fires by depriving them of oxygen. It doesn't burn itself.


How reliable are the Fireboy engine shutdown systems? Well, I suppose the Cummins type of energize to run is more reliable than the Yanmar type of energize to stop. No matter how the Cummins type loses its electrical energization- an electrical failure due to the fire or the Fireboy doing it, the engine will stop. But I will be that the difference is not material.


So, hook up your Fireboy to the engine stop system.


David

Click to expand...

Not to hijack the thread but I also have Cummins with the "energized on"
And fire boy system.
Anyone ever have their fuel solenoid fail?
I always liked my detroits, on previous boat, for that reason they were energize to shut down.
Just another thing to go wrong, when picking up my new to me boat starboard fuel solenoid had a loose wire and shut down. Fortunately only took me a few mins to diagnose and back on the trail.
I've thought about carrying a spare but cummins told mr they sell very few of them.
Experiences?

Ransom said:

Ken? Do you remember the Approximate Cost of installing a FireBoy System?

Click to expand...

PO did it so I'm not sure though I should have the receipt someplace. I think the equipment alone was in the 4-5k range plus installation.

Ken

Folks that have fuel tanks that are connected from a low point can find fuel valves made for house tanks that will self close in a fire.

$10-$15 or so might be a help.

Many newer fire control systems use FM-200 which is heptofleuropropane since Halon was ruled bad for the environment.

This will support life but not fire. You have to stop the engine and blowers to allow it to displace the air in the ER to stop the fire. The right way has dampers controlled by the fire control system that shut before deployment.

The systems are easy to install. When I repowered I put in a Fireboy system. The procedure is basically as follows:

1. Mount the fire extinguisher bottle
2. Run wires from the bottle to the shut down control and to the helm station control/override panel
3. Run wires from the shut down control to the engine shut down solenoid and to anything else that needs to be shut down (blower, etc.). The only tricky part is connecting the wiring to the engine shut down solenoid properly, but that is easy if you have the wiring diagram for your engine.

My Fireboy shut down system has multiple relays to shut down blowers and the engine stop solenoid. Options are available for NO and NC solenoids (i.e., remove power to stop and add power to stop).

On mine the hardest part was pulling the wires in.