Carbon Monoxide

[Tim22]

Recently the CO alarm in the boat has started going off. Curiously, it doesn't go off until several hours after the engine has been shut down and the boat closed up. Thinking that it might be due to the age of the alarm I replaced it but the problem persists. I also bought a second, cheaper, home alarm that displays the ppm to verify the presence of CO, which it did. Since then I have been trying to track down the source by placing the home alarm in various places around the boat while the engine is running. The engine compartment, the bilge where the exhaust hose runs, and the stern at the exhaust discharge have all yielded readings of 0 ppm.

The boat is a Hunter 310 and the engine is a Yanmar 2gm20f. I would be grateful of any suggestions as to how to track this down, and what the likely failure points in the exhaust system are.

Many thanks
Tim

 

[Maine Sail]

Turn off your battery charger..

 

[Ralph Johnstone]

Check here and refer to Rich's post #7 for a possible solution.

http://forums.sailboatowners.com/index.php?threads/where-is-the-co-coming-from.179300/&highlight=CO

 

[Tim22]

Thanks Maine & Ralph.
I removed all the solvents, cleaners etc. From the boat after the first alarm. I will check again and try shutting down the charger when I go to the boat tomorrow. The batteries are in an aft cockpit locker well removed from the alarm location. There is, however, a small opening to a separate locker below where the charger is located. This locker is separated from the aft cabin by a bulkhead that is partly open to the rest of the boat at the bilge level so theoretically CO could find it's way into the aft cabin from the battery compartment. I'll let you know what I find.

Tim

 

[Tim22]

Yesterday we went out and ran the engine for about half an hour to 45 minutes. Upon returning I left the battery charger off and closed up the boat. Today there was no alarm. This would seem to indicate, as Maine suggests, that the problem is with the batteries. I did not run the engine today but did turn the charger back on so if the alarm goes off this should confirm that the problem is with the charging. I'll check it later today or tomorrow.

If this is a problem with the charging is it indicative of bad batteries, or a bad charger?

Thanks
Tim

 

[Tim22]

Went to the boat today and the alarm was going off. The engine has not run since Saturday and the charger has been on which confirms the batteries as the cause of the alarm going off.

Before replacing the batteries, is it likely that there is a problem with the charger that would cause the batteries to gas more than normal? The charger is an Intelli-Power Marine and is about 5 years old.

Thanks
Tim

 

[Hello Below]

Went to the boat today and the alarm was going off. The engine has not run since Saturday and the charger has been on which confirms the batteries as the cause of the alarm going off.

Before replacing the batteries, is it likely that there is a problem with the charger that would cause the batteries to gas more than normal? The charger is an Intelli-Power Marine and is about 5 years old.

Thanks
Tim

Tim,
I am following this post very carefully.

Often (as in many times) when I come alongside, plug in the shore cable, turn on the battery charger (absorption = 4 hours @ 14.7V), close up the boat and leave, I will get a call from the marina staff reporting that my boat is beeping . . . again. Last night after returning from a month of cruising, I closed the boat up and about two hours later the call came in. I have 3 Safe-T-Alert CO monitors on board (as fitted from Hunter new in 2012). Unfortunately even if the CO level drops to zero, the alarm continues until they are physically reset. When I returned to the boat last night all 3 were merrily beeping away. I reset the monitors, cracked a hatch and turned a fan on for about 30 minutes. I closed up the boat and went home. All was happy after that. It has never happened when we are present on the boat as there will always be a hatch and/or a port light and/or the companionway hatch opened.

I have a 120v ac CO alarm/detector at home that provides a digital numeric readout. I must take it to the boat to get a better understanding as to what levels we are talking about. The monitors themselves have a rudimentary memory feature which tells me if the peak level was low, medium or high (time weighted). It has always been low or less than 100 ppm. But how low and yet still sets the alarms off, I don't know.

Hopefully other members will wade in here and speak to the seriousness of the alarm, cause of the alarm and maybe solution as to how to correct.

 

[Ron20324]

[QUOTE... Hopefully other members will wade in here and speak to the seriousness of the alarm, cause of the alarm and maybe solution as to how to correct.[/QUOTE]

My initial thought is why worry about it if no one is on the boat. If the marina and others are hearing the alarm, why not just shut it off when not on the boat? You know the cause.

 

[Tim22]

Hi Ron
The main reason I don't want to ignore it at the moment is that I would like to be sure that the charger is not damaging the batteries by causing them to gas excessively. The boat has gone three seasons since I bought it with the same batteries, the same charger, and pretty much the same charging routine and no alarms. Don't know what happened before that. If there is a way to determine that the charger is not at fault I am pretty much happy to ignore it.

Thanks
Tim

 

[Hello Below]

If the marina and others are hearing the alarm, why not just shut it off when not on the boat?

I would love to be able to switch them off but I can't. All 3 of the detectors are wired through a single resettable push button breaker.

You know the cause

Sorry, poor wording.

The detectors are doing their job. What I should be asking, and the OP has alluded to, is what is causing the off gasing that causes the alarm? In my case, is it one or more of the 4 FLA GC batteries off gasing abnormally, the ProTech 1230 charger overcharging, over sensitive detector(s), positioning of the batteries in the salon, closed up boat with a single cowl vent or something else?

 

[JamesG161]

If there is a way to determine that the charger is not at fault I am pretty much happy to ignore it.

Don't ignore it!
Use your DVM to check the maintenance charge (≈13.5VDC) when you arrive to reset you alarms (higher voltage says you probably need to read the charger owners manual and do a factory RESET).
If wet cell batteries, open a cap and see if they are gassing. Get one of the el cheapo multi colored floating ball, battery acid tester and verify if you have a good battery (auto zone, chinamart, napa).

With charger OFF, no shore power, no genset, turn on some DC draws, Check you Battery with DVM to see if the VDC is dropping too fast, go chat with other boaters, come back a check batts VDC again. Go eat lunch, check batts again.... You get my point? Record you info and if you can monitor DC amps draw in all this testing.
Record time, VDC and AMP draw .... The plot sould follow a known Lead/Acid curve.

What is the brand of you CO detectors? If the are ionization type, usually the detector has 10 years life.
Jim...

 

[Tim22]

A new wrinkle! I continue to believe the alarms are being triggered by excessive battery gassing. For most of the testing I have had the Adler Barbour fridge running to provide a load on the battery. As a final test I turned the fridge off and turned on all the lights to provide some load. After 24 hours the alarm had not gone off and the portable detector was registering 0 ppm. I left the lights on and moved the portable alarm to the battery compartment and will check again today.
I am beginning to think that the added draw of the fridge, or the on off cycling may be causing the charger into a more aggressive charging cycle which is causing the gassing.

The alarm is a safe- t-alert and is new. I replaced the old one when it went off for the first time a couple of weeks ago.

Tim

 

[JamesG161]

The alarm is a safe- t-alert and is new.

I went to the manufacture's web site
http://www.mtiindustries.com
Depends on you model, but I read Marine CO model. I couldn't find the type of detection method.
But...
In that manual they emphasized it was a CO/Propane detector ONLY! Not Hydrogen gassing or smoke!
Check which Model you have to help clarify what you are detecting.
Jim...

 

[CloudDiver]

Not sure if this helps but I had what I think is a similar problem with the house batteries in my Toyhauler (RV). Same as this case, alarm was going off but no genset running or other sources of carbon monoxide present. Only difference was I got the hint of a sulfur smell. The batteries are in a separated compartment but I could smell them from the coach, very hot and out-gassing badly (sealed OPTIMA Blue Tops). My best explanation is that they were in fact wired in parallel, but not the correct way... they should have the leads coming off opposite corners, not both leads off the same side of one battery. This caused un-even charging and cooked the battery that was first in-steam.
I'm not totally sure there wasn't a problem with the charger, since I had removed the cooked battery and extra parallel leads and just went with a single battery. I got another few camping trips out of that battery, but it ended up getting cooked as well... $440 worth of Optima Blue Tops, plastic tops all bubbled up, destroyed after only 3 years, only about a 30 days total camping. I got the charging system board replaced on warranty.... they did a one for one swap but the technician never emailed me back to say if my old board had failed any diagnostics testing.
I can't be sure if the charger's auto-off feature was working or not, but I do know the batteries were not wired correctly. Had I read MainSail's articles 5 years ago when the dual battery system was installed I could have easily identified the problem. If the batteries had still cooked when correctly wired, then I could more sure it was a faulty charger and warranty would have had to also replace my batteries rather than just the charger board. If it was my fault (and I think it is) because of the way the batteries were wired, then I consider myself lucky that they were so gracious to send me the new board.

 

[Tim22]

I went to the manufacture's web site
http://www.mtiindustries.com
Depends on you model, but I read Marine CO model. I couldn't find the type of detection method.
But...
In that manual they emphasized it was a CO/Propane detector ONLY! Not Hydrogen gassing or smoke!
Check which Model you have to help clarify what you are detecting.
Jim...

Hi Jim
Detector is CO http://www.mtiindustries.com/products.asp?cf=1&ti=0&ci=2&si=13&pi=69

I had ruled out the batteries due to the description in the manual but reconsidered when Maine suggested shutting down the charger which seems to have stopped the alarms. However, I have just returned from the boat where the charger has been on for the past 48 hours but with only the load of the lights and there was no alarm. Also, the reading on the portable co alarm which I left in the battery compartment was reading 0 ppm.

Thanks
Tim

 

[JamesG161]

After reading that Owners guide, there is a trouble shooting section of colored blinking lights and/or chirps. If none of those are happening when you arrive at a "alarming" boat (Don't reset alarm so quickly), then I would suggest an email or phone contact with them, with these thoughts.
1) It appears JUST CO is detected and no other gases. True?
2) It is NOT ionization type (radioactive isotope of Americium used). Chemical type detector?
3) Are there other fumes that cause interference?
4) Tell them problem.
5) What is the ANSI, UL, etc standard they followed to call it Marine use?

If your Portable had not detected CO, I would have thought a (blue/yellow wire) wiring problem.

I have just returned from the boat where the charger has been on for the past 48 hours but with only the load of the lights and there was no alarm.

I may have been a transient CO which could come from a neighbors barbecue grill.

The reason CO is poisonous is it wants to be CO2 (stable), thus CO grabs your blood's O2 and you are poisoned.
But a chemical detector can't separate a complex carbon with a CO bond. Burnt dust on your toaster elements, Heat pump AC, melting wiring insulation, neighbors engine exhaust, propane flame, overheating charger, Large AC power draw across a dusty transformer, a prankster at the marina.

CO is orderless, Do you smell anything when the CO alarm is off?
Jim...

 

[Tim22]

Many thanks for all the help and suggestions.

After a week of not running the engine, and 4 days after turning off the fridge the alarm went off. The portable in the battery compartment showed 41 ppm. I have checked the batteries with the hydrometer and found 1 cell in each that is borderline.

I am more or less satisfied that the problem is battery related and, as the short Canadian summer is moving along I must too! after much research I have decided to replace the charger with a Sterling Ultra 30 Amp and will replace the batteries once I'm sure that the new charger is working properly. No doubt I will have many questions regarding the installation but, for the moment, will re read Maine's excellent article on the subject.

Tim

 

[Gunni]

Good plan. You know you need new batteries, and smart chargers have gotten a lot smarter. Do a system upgrade.

 

[Kings Gambit]

The reason CO is poisonous is it wants to be CO2 (stable), thus CO grabs your blood's O2 and you are poisoned.
But a chemical detector can't separate a complex carbon with a CO bond.
CO is orderless, Do you smell anything when the CO alarm is off?
Jim...

Jim,
CO essentially binds irreversibly with blood hemoglobin (Hb); so it overwhelms the oxy-hemoglobin bindings sites until nearly no oxygen can be bound, and the victim suffocates. The hemoglobin bound-up by CO has be to destroyed by the body, and new red cells containing new hemoglobin have to be produced. Giving a victim oxygen helps to give oxygen a better chance at the remaining available Hb sites after CO exposure, plus it saturates the plasma with oxygen to get more of it to the cells that way, until the victim can recover.

 

[JamesG161]

CO essentially binds irreversibly with blood hemoglobin (Hb); so it overwhelms the oxy-hemoglobin bindings sites until nearly no oxygen can be bound, and the victim suffocates. The hemoglobin bound-up by CO has be to destroyed by the body, and new red cells containing new hemoglobin have to be produced. Giving a victim oxygen helps to give oxygen a better chance at the remaining available Hb sites after CO exposure, plus it saturates the plasma with oxygen to get more of it to the cells that way, until the victim can recover.

That is what I said, Kinda.

Good details on the mechanism. CO wants to chemically bond. CO2 doesn't, whew, or we would poison ourselves.
Jim...

PS: @Tim22 manual says a detection threshold of ±400ppm CO.