Sources of CO

[Taras]

Hey all,
After the big boat fire in So Cal, I decided to install 8 new smoke/CO detectors throughout my vessel. They are the wireless kind that talk to each other. If one goes off, they all go off.
My buddy was walking by my boat, called me and said my alarms were going off (I was 3 hours away and wasn’t going to be back on the boat for a week). He went inside and the alarms were sounding “carbon monoxide dectected” and were beeping like mad. I had him pull the batteries out of each one at a time. Couldn’t tell which one actually started the alarm.
Anyway, obviously nothing was running on boat. Everything shut down. Just the fridge circuit and battery chargers on. All windows closed.
Question: what can cause the CO to go off? What source?

 

[RT Firefly]

Greetings,
Mr. T. Battery charger most probably. Don't know the "chemistry" but I don't think it's that uncommon.

 

[psneeld]

Agreed, I have had at least 4 times over the last 20 years where the CO detectors early warned of batteries starting to over charge/or bad cells.


Maybe once for a gasser a few boats down idling forever on a calm day.

 

[klee wyck]

Is is pretty likely that this was not carbon monoxide from your boat if there was no combustion occurring anwhere at the time so yours is a valid question.
If the batteries are LA, they will not emit CO when charging as there is no source of carbon in them. I am not familiar with other battery chemistry.
However, LA batteries can emit Hydrogen . CO monitors cannot generally distinguish between hydrogen gas and carbon monoxide and will alarm in the presence of either. So I agree with earlier posts, likely batteries, but not likely CO.

 

[Comodave]

Most likely the battery charger but maybe a gas powered boat idling nearby.

 

[kchace]

Battery out gassing excessively can definitely set off a co2 alarm. Happened to me too.

 

[SteveK]

Can we agree the battery charger may be the originator but it was the batteries off gassing that triggered the alarm.

 

[Flatswing]

Here's one more cause: my holding tank (full of urine only) leaked. Set the CO monitors off consistently until I pumped out & really paired it!

 

[psneeld]

Can we agree the battery charger may be the originator but it was the batteries off gassing that triggered the alarm.

Not really...have had both the charger and bad batteries be the source....the charger being fine sometimes.

 

[SteveK]

Not really...have had both the charger and bad batteries be the source....the charger being fine sometimes.

How does a charger put out CO?

 

[rslifkin]

How does a charger put out CO?

It doesn't. But batteries off-gassing can be caused either by a bad charger or a failing battery (with a healthy charger).

 

[RT Firefly]

Greetings,
Mr. SV. Please re-read post #'s 4 & 8. CO detectors can trigger from sources other than CO.

 

[SteveK]

Greetings,
Mr. SV. Please re-read post #'s 4 & 8. CO detectors can trigger from sources other than CO.

Please re read 7 & 11.
Other sources introducing a gas which the sensor reads as CO. Just like a smoke detector will sound off when silverfish crawl over the sensor.
However a charger overheated and caused gas off from wire windings perhaps. Would that then be a failed charger, or a normal event.

 

[RT Firefly]

Greetings,
Mr. SV. I don't know what you're fishing for but several viable sources have been suggested regarding the OP's question any one of which may be the answer but since the OP mentioned that the only things that were on were his fridge and charger it seems to be the MOST likely source, to me, at least.


Might be his fridge sprung a leak and the escaping Freon caused the alarm or perhaps a Harrier jet hovering over his boat....


And, no, I wouldn't consider a failed or overheating charger to be a "normal" event.

 

[SteveK]

Most likely the battery charger but maybe a gas powered boat idling nearby.

Can we agree the battery charger may be the originator but it was the batteries off gassing that triggered the alarm.

Not really...have had both the charger and bad batteries be the source....the charger being fine sometimes.

Mr. RT. Are we reading the same thread?
Yes the OP has had plenty of sound suggestions.
Can the charger emit a gas that the sensor reacts to?

 

[CaptTom]

I've had CO alarms go off from outgassing FLA batteries, too.

But also be aware that there are "marine" CO alarms which work differently than home alarms. I'm no expert, but as I understand it, they marine ones are more tolerant of small, transient amounts of CO, like a passing outboard, while home units will continue to count accumulated amounts and then alarm when some threshold is reached.

If these are not marketed as marine detectors, you may end up replacing them all.

 

[rslifkin]

Most of the newer home detectors work similarly to the marine units where they're time averaged. A low level for a long enough time will trigger the alarm, or a higher level for a shorter time will trigger them. So brief low level transients shouldn't do it.

 

[RT Firefly]

Greetings,
Mr. SV. As I stated, I don't know the chemistry or I suppose, perhaps, more accurately the electro-chemistry involved in the workings of the CO sensor nor what the trigger mechanism/threshold is for anything the sensor may detect.


Until such time that Mr. T returns to his boat and does an assessment of conditions aboard we can only speculate but from the initial evidence provided, baring silverfish, I still think batteries are the most likely cause.

 

[SteveK]

Greetings,
Mr. T. Battery charger most probably. Don't know the "chemistry" but I don't think it's that uncommon.

Greetings,
Mr. SV. As I stated, I don't know the chemistry or I suppose, perhaps, more accurately the electro-chemistry involved in the workings of the CO sensor nor what the trigger mechanism/threshold is for anything the sensor may detect.


Until such time that Mr. T returns to his boat and does an assessment of conditions aboard we can only speculate but from the initial evidence provided, baring silverfish, I still think batteries are the most likely cause.

I agree with bolded as probable cause. But not the charger itself without the battery. I was waiting to learn something new in that regard.

 

[RT Firefly]

Greetings,
Mr. SV. Ah. I see where the confusion arose. My apologies.

 

[High Wire]

Agree with hydrogen offgas from an overcharged battery cell. I have had it happen on an AGM 8D gone bad. Yes it could be the charger driving battery voltage above 14.0 volts for excessive time. Maybe it failed to revert to Float mode after reaching full charge.
In summary, removing the smoke detector batteries silenced the alarm but the initial condition still exists.

 

[O C Diver]

The other thing that can trigger these detectors is a very small insect inside the device. We have had that problem with a combination detector in a family home on Martha's vineyard. The PIA part is finding which detector has the insect and evicting it.

Ted

 

[Taras]

Thanks all for your thoughts.
I will be returning to the boat this weekend to check things out.
I just topped off my 8D flooded batteries prior to me exiting the boat.
Then, my buddy calls me and tells me the alarms are going off.
I’m thinking you guys might be right. Hydrogen off gassing......?

 

[Steve DAntonio]

I've had CO alarms go off from outgassing FLA batteries, too.

But also be aware that there are "marine" CO alarms which work differently than home alarms. I'm no expert, but as I understand it, they marine ones are more tolerant of small, transient amounts of CO, like a passing outboard, while home units will continue to count accumulated amounts and then alarm when some threshold is reached.

If these are not marketed as marine detectors, you may end up replacing them all.

Time weighted averaging is a a process used by most marine CO detectors, household alarms may use this as well to prevent false alarms.

I have installed household combination smoke/co detectors in scores of vessels with few false alarm issues.

To be clear, an overcharged FLA battery emits excessive hydrogen gas, which is known to trigger CO alarms.

Also, tightly closed up vessel, with carpet, and other upholstery, particularity in hot climates, can off gas enough to trigger an alarm.

Finally, CO from nearby vessels can trigger alarms if the alarm equipped vessel is adjacent of downwind, this scenario has actually been responsible for deaths. Not suggesting that's the case here, just pointing out this is possible, and it's why ABYC draws no distinction between vessels that have CO-producing devices and those that don't. All vessels with enclosed cabins need a CO detector(s).

More on the subject https://stevedmarineconsulting.com/co-poisoning/

As an aside, diesel exhaust produces very little CO, in my research I have been unable to find any deaths related to diesel-produced CO.

(In Taiwan at the Ta Shing Yard)

 

[Airstream345]

Curious which linked system you installed. Our new to us KK came with neither smoke nor CO detectors and I’ve been shopping for some to install.

 

[boatpoker]

As an aside, diesel exhaust produces very little CO, in my research I have been unable to find any deaths related to diesel-produced CO.

Neither have I been able to find a fatality connected to diesel produced CO however I once did some work for a professor of haematology.

He told me that he knew of no valid studies with diesel exposure over time and that even if it caused no fatalities a severe reaction was possible if not likely with extended low level CO.

He explained that it takes up to two weeks for the effects of CO to clear from the blood. With that in mind a snowbird run from Toronto to the Bahamas with a low level CO leak could make for a very sick crew.

 

[RT Firefly]

Greetings,
Mr. bp. I also understand CO is cumulative. I suppose with your scenario (TO to the Bahamas) one's blood might become very close to the saturation point and any incident of "extra" CO exposure that might otherwise be somewhat benign could easily be fatal. Good point.

 

[Taras]

So I was on my vessel this weekend and sure enough, both of the 8D start batteries (which I recently topped off) were in fact very hot and off gassing hydrogen. Those batteries are shot. Time to replace. Battery charger was just pumping juice into them.
I’m sure that’s what triggered my new Kiddie smoke/CO detectors.
Thanks all for the help!

 

[audioshark]

how to determine the detector that caused the alarm

Generally they all have a light on them sometimes two. Look at the alarm if they are going off and blinking green, one should be blinking red. That is the one that caused them all to go off. Once you press the button and reset them or pull out the batteries you will have to wait until they go off again.

 

[Steve DAntonio]

Curious which linked system you installed. Our new to us KK came with neither smoke nor CO detectors and I’ve been shopping for some to install.

Smoke and CO detection is a requirement for ABYC compliance. I know KKY doesn't profess full ABYC compliance, but you might ask for their take in this, I'd think they'd want to comply.

More on smoke detectors here https://stevedmarineconsulting.com/wp-content/uploads/2018/06/Smoke-Detectors-gearhead-may-2018.pdf

(In Taiwan at the Ta Shing Yard)