Carbon monoxide on boats

[Timx]

Hi , I have two co 1 alarms on nb, this year, I had problems with Morso stove. Kept on getting smoke blowing back into boat.

tried a few different ways to stop it. Eventually found the problem , and sorted it with a cowl on top of chimney. All good.

however when trying to sort it unsuccessfully initially, my alarm went off during the night. Well one did the other didn’t but was showing a lower reading. Since then I have been keeping an eye on the more sensitive alarm. It reads between 18 and 27, the higher reading causes headaches and I have to open windows overnight, 18 is usually the morning reading.

is this normal .?

should it be 0 all the time ?

Had the stove 9 years, never noticed a problem before, but never monitored it before.

would be interested in others findings and views.

[MtB]

4 minutes ago, Timx said:

Hi , I have two co 1 alarms on nb, this year, I had problems with Morso stove. Kept on getting smoke blowing back into boat.

 

This is Bad News, shouldn't do that.

 

Take the flue baffle out and I predict you'll find a kg or so of soot and rust almost blocking the throat.

 

 

 

[Guest]

12 minutes ago, Timx said:

Hi , I have two co 1 alarms on nb, this year, I had problems with Morso stove. Kept on getting smoke blowing back into boat.

tried a few different ways to stop it. Eventually found the problem , and sorted it with a cowl on top of chimney. All good.

however when trying to sort it unsuccessfully initially, my alarm went off during the night. Well one did the other didn’t but was showing a lower reading. Since then I have been keeping an eye on the more sensitive alarm. It reads between 18 and 27, the higher reading causes headaches and I have to open windows overnight, 18 is usually the morning reading.

is this normal .?

should it be 0 all the time ?

Had the stove 9 years, never noticed a problem before, but never monitored it before.

would be interested in others findings and views.

 

How often do you give your stove a good clean out?

 

If not often crud will build up and restrict flow.

 

Our baffle plate comes out once every couple of weeks for a good scrape off.

 

The cumulative effects of CO can be very dangerous. If you are getting head aches you need to sort it immediately.

[bizzard]

If the Morso stove has no back boiler tank but a half moon shaped throat plate instead, remove it, two nuts. These plates are only for use in houses with much taller flue's. Left in will leave loads of crud on top of it and in the flue pipe.

[Timx]

48 minutes ago, MtB said:

 

This is Bad News, shouldn't do that.

 

Take the flue baffle out and I predict you'll find a kg or so of soot and rust almost blocking the throat.

 

 

 

Thanks, but have done that, and swept chimney twice.

29 minutes ago, bizzard said:

If the Morso stove has no back boiler tank but a half moon shaped throat plate instead, remove it, two nuts. These plates are only for use in houses with much taller flue's. Left in will leave loads of crud on top of it and in the flue pipe.

Thanks, that throat plate is already removed.

[nicknorman]

Our CO detector always reads zero. Well it should do. A couple of years ago it started showing a reading whenever the stove door was opened to refuel etc - and it is not close to the stove.

 

To cut a long story short I removed the flue pipe because it was choked up with a very hard concrete-like deposit and at one point near the stove, the clear diameter was only about an inch. Cleared it all out with a long chisel etc and since then it has been fine with always 0 on the CO detector.

 

So probably your flue is severely restricted. Personally I disagree about removing the baffle plate, the plate is there for a reason and helps improve the efficiency of the stove, but you do need to clean out the space above the baffle plate from time to time.

2 minutes ago, Timx said:

Thanks, but have done that, and swept chimney twice.

Thanks, that throat plate is already removed.

If it is anything like our flue was, sweeping it is ineffective because the deposits are rock hard.

[Timx]

39 minutes ago, MJG said:

 

How often do you give your stove a good clean out?

 

If not often crud will build up and restrict flow.

 

Our baffle plate comes out once every couple of weeks for a good scrape off.

 

The cumulative effects of CO can be very dangerous. If you are getting head aches you need to sort it immediately.

Thanks, every couple of weeks, surprises me, never had a problem before in nine years, but thanks will look at it, MTB said much the same so will look at it., so what is a normal level on your boat, is it 0. Looking on net below 30 says ok , but obviously not if getting headaches.

[bizzard]

5 minutes ago, nicknorman said:

Our CO detector always reads zero. Well it should do. A couple of years ago it started showing a reading whenever the stove door was opened to refuel etc - and it is not close to the stove.

 

To cut a long story short I removed the flue pipe because it was choked up with a very hard concrete-like deposit and at one point near the stove, the clear diameter was only about an inch. Cleared it all out with a long chisel etc and since then it has been fine with always 0 on the CO detector.

 

So probably your flue is severely restricted. Personally I disagree about removing the baffle plate, the plate is there for a reason and helps improve the efficiency of the stove, but you do need to clean out the space above the baffle plate from time to time.

If it is anything like our flue was, sweeping it is ineffective because the deposits are rock hard.

Usually caused by feeding wet or damp smokeless fuel in the stove.

[Guest]

10 minutes ago, Timx said:

Thanks, every couple of weeks, surprises me, never had a problem before in nine years, but thanks will look at it, MTB said much the same so will look at it., so what is a normal level on your boat, is it 0. Looking on net below 30 says ok , but obviously not if getting headaches.

 

When we had our boat I think the max got up to about 20. But we never had headaches.

 

Now at home our CO alarm only registers zero.

 

If you are concerned enough to ask on here about CO levels that cause headaches then it's time to stop using your stove until you have identified the source of the problem.

[booke23]

47 minutes ago, MJG said:

If you are concerned enough to ask on here about CO levels that cause headaches then it's time to stop using your stove until you have identified the source of the problem.

 

Agreed. To the OP, leave no stone unturned….get the baffle plate out and shine a light up the chimney and go outside and look down it to confirm there is no restriction. Check all rope seals and glass for condition….on a 9 year old stove they’ll probably need replacing if they haven’t already.   

[blackrose]

What type of cowl did you put on top of the chimney? Although you say it's improved the situation that may be due to coincidental reasons. How's the draw on the stove? Does it draw well? If so the problem is unlikely to be due to door seals, etc and may be higher up, but I'd definitely check and reseal the stove collar seal and also the deck/roof collar seal at the top.

 

Also what other appliances do you have onboard? We're assuming it's the stove which is the chief suspect but who knows? Are any gas pilot lights left on overnight for example?

[BEngo]

When you have boogied out the flue, go round the stove with a good torch.  Check that all the panels are crack free and that the joints are properly sealed.  Morso stoves are good, but they are very prone to cracks where the bolts hold the front and rear panels to the top and bottom, especially if rust has built up in the joins.

Check also the rear flue entry.  The ssealing plate is only held on by two small bplts and these again do not like it if rust has built up in the join.

 

N

[Momac]

9 hours ago, Timx said:

 

should it be 0 all the time ?

Certainly you should not be getting alarms. 

Please do not use the stove that you have identified is the cause of the problem.

 

There are very serious health risks from prolonged exposure to CO

https://www2.hse.ie/conditions/carbon-monoxide-poisoning/#:~:text=Prolonged exposure to carbon monoxide,vision loss and hearing loss.

 

 

[Cheese]

Can you use your more sensitive alarm to narrow down where CO might be leaking from? Around stove doors? Flue base? Higher up? ...

[Sea Dog]

I have 2 CO alarms, one near the stove one at head height in the bedroom. Both normally read zero, although I think I've seen single figures on the one by the stove once or twice when taking far too long refuelling. 

[ditchcrawler]

There is another reason for CO alarms going off, dying Lead Acid Batteries gassing.

[Momac]

Just now, ditchcrawler said:

There is another reason for CO alarms going off, dying Lead Acid Batteries gassing.

In this case the OP seems sure the stove is the source but all other possibilities should of course be considered.

[MtB]

2 minutes ago, ditchcrawler said:

There is another reason for CO alarms going off, dying Lead Acid Batteries gassing.

 

And another. The cooker.

 

Anything involving flame chilling, e.g. flames playing on metal surfaces such as gas rings heating kettles, or grills, chucks out CO. So don't be surprised if the CO monitor shows a result when you're cooking. 

 

 

 

[alias]

3 hours ago, MtB said:

 

And another. The cooker.

 

Anything involving flame chilling, e.g. flames playing on metal surfaces such as gas rings heating kettles, or grills, chucks out CO. So don't be surprised if the CO monitor shows a result when you're cooking. 

 

 

Yet another is tobacco smoke. Not enough carbon monoxide to cause an acute problem on its own, but might be exacerbating emissions from other sources.

 

 

[nicknorman]

3 hours ago, MtB said:

 

And another. The cooker.

 

Anything involving flame chilling, e.g. flames playing on metal surfaces such as gas rings heating kettles, or grills, chucks out CO. So don't be surprised if the CO monitor shows a result when you're cooking. 

 

This is of course correct, but the amounts involved are very small. Our CO detector is within about 5 feet of the hob but it has never come off 0 during cooking. Nor even when I bring it closer. Presumably with the CO being mixed with hot air and hot CO2, it rises quickly to the top of the cabin and then out through a mushroom vent.

[Alan de Enfield]

2 minutes ago, alias said:

 

Yet another is tobacco smoke. Not enough carbon monoxide to cause an acute problem on its own, but might be exacerbating emissions from other sources.

 

 

 

Interesting you mention that, I am in the process of taking some advanced diving theroy exams and part of the 'medical' section mentions not to 'have a quick cigarette before a dive'.

 

Cigarette smoke has some 400ppm of CO,

It can take 24 hourse to disperse out of your system

CO attaches itself to the haemoglobin more readily than O2 so reduces the oxygen in your system, whilst increasing the Nitrogen.

 

That is why smokers easily get short of breath

 

Lots of Nitrogen and not much Oxygen is not conducive to a long life when under water.

[MtB]

16 minutes ago, nicknorman said:

This is of course correct, but the amounts involved are very small.

 

Not necessarily. People have died from the CO coming off a cooker grill. Admittedly they closed the grill door while cooking in contravention of the Instructions For Use, but the CO involved cannot have been trivial. 

 

 

[jonathanA]

My CO monitor reads 0 all the time. The only time and it's pretty rare that I get anyvsmoke out of the morso is whe  I open the main door not long after lighting with no draught from the bottom door or bottom vent. 

 

Think I'm with the others seems like a draw problem to me.  Even when my seals have been ready for replacing I've not any leakage. 

 

The rear flue cover plate is a good call as it might not be obvious from inside the stove that it's not sealed properly. Mine actually fell off completely .. that was quite noticeable!

[alias]

5 minutes ago, jonathanA said:

The rear flue cover plate is a good call as it might not be obvious from inside the stove that it's not sealed properly. Mine actually fell off completely .. that was quite noticeable!

 

Mine too, in this case from an Arada stove with two cast iron lugs on the cover plate, when one of these snapped off for some reason. In my case there was no sign of smoke inside but when I checked (after putting the fire out!) the CO meter nearby was reading 20 ppm instead of the usual zero.  

 

[nicknorman]

29 minutes ago, MtB said:

 

Not necessarily. People have died from the CO coming off a cooker grill. Admittedly they closed the grill door while cooking in contravention of the Instructions For Use, but the CO involved cannot have been trivial. 

 

Yes but that was not due to CO from a flame touching a metal pan etc. That was from severe incomplete combustion caused by lack of oxygen due to closing the drill door. No doubt had they been able to see it the flame would have been yellow and sooty. My “very small” relates to the CO produced when an otherwise good flame plays on a saucepan etc.

 

Certainly, any time there is a “bad flame” (yellow and sooty) there is plenty of CO being emitted.