CO (the deadly gas)

[bottle]

I know we have discussed CO before in connection with stoves etc. but just to tell a little story that happened to me.

 

Over the last couple of days a smell (fuel) emitted from the stove whenever the doors were opened to refuel and the CO alarm showed a figure of about 20 ppm, the second CO alarm (just past its replace date) showed nothing. ( the second one will be replaced)

 

The alarm always returned to zero quite quickly and the smell disappeared, the alarm remained at zero at all times with the stove doors closed.

 

Yesterday the stove did not draw well,

 

Not unduly worried but this morning, the smell and the alarm ( 20 ppm) returned before I opened the doors and had only opened the bottom vent to 'wake' the fire. It was zero when I got up.

 

So out in the pouring rain, I got a boat pole and put it down the chimney/ flue, there was a partial blockage towards the top.

 

I had as always checked and cleaned the chimney/flue before the first lighting this season (about a month ago) and have cleaned it since.

 

 

 

 

 

 

[dogless]

Glad to be reading your report of what happened, rather than someone elses's

Thank you for the timely reminder and information. It can be too easy to slip into

a casual, relaxed attitude regarding these things.

Hope you have no further trouble.

Rog

[John V]

I have CO detectors all over the place, it's insidious nature is something I am very aware of.

Several years ago, I went with a friend to their elderly mother's house, my friends son and girlfriend were there at the same time.

After our evening meal we went into the sitting room where there was a freshly lit fire in the multifuel stove.

We were all sat comfortable and warm and dozing when the son's girlfriend announced that she had a stinking headache and was going to bed.

A short time later I suddenly realised that the mother was not just asleep but unconscious and the rest of us were heading in that direction, I was fortunately still with it enough to open all the doors and windows and call for an ambulance. All of us required treatment, my friend and her mother were the worst but all required a trip in the ambulance to Bishops Stortford hospital.

It was far too close a call for comfort.

(Unfortunately my friends mother died shortly after and we often discussed the possibility of this incident having some bearing)

[nicknorman]

Fake Britain (yes I know, daytime TV!) had a thing about fake detectors the other day. They looked ok but didn't meet the requirements for sensitivity and in particular it was mentioned that the sensors get "poisoned" by CO and thus, following a significant escape of CO and some recovery time, the detector may be much less sensitive for a subsequent occurrence. This repeat test being part of the U.K. standard which these fake detectors failed. Some of them just plain didn't work at all.

 

Anyway the point is that detector sensors DO have a limited life and that life is probably further shortened by significant contamination with CO.

 

Moral is to buy from a reputable source (not eBay unless you are sure of the provenance!) and change at or before the expiry date.

Edited November 29, 2015 by nicknorman

[John V]

snip<

Moral is to buy from a reputable source (not eBay unless you are sure of the provenance!) and change at or before the expiry date.

 

That is the great advantage of the type with a non-replaceable battery

[the barnacle]

strange for a flue to block so quickly? - what diameter is it? what have you been burning, fresh wood?

[Bee]

I think I have posted this before but some years ago the stove suddenly began to smoke badly and would not stop. Hopped out and had a look to find that the corner of a tarpaulin that was covering some wood had been flipped over the chimney by the wind. If the stove had been burning cleanly and not making a bit of smoke ....

[bottle]

I agree strange, never happened in the last six years as CCing live-aboard and obviously will be ultra careful until satisfied there is not a problem.

 

Never burn wood, only Excel, flue approximately 4+"

[the barnacle]

I agree strange, never happened in the last six years as CCing live-aboard and obviously will be ultra careful until satisfied there is not a problem.

 

Never burn wood, only Excel, flue approximately 4+"

 

Thank you for the reply - last week in the morning i heard a noise in my log burner in my workshop, i opened the door and a black bird was sitting in the ashes - it must of fallen down the flue in the night - after a few minutes it flew out.

[nicknorman]

Thank you for the reply - last week in the morning i heard a noise in my log burner in my workshop, i opened the door and a black bird was sitting in the ashes - it must of fallen down the flue in the night - after a few minutes it flew out.

What colour was it before it fell down the flue?

[the barnacle]

What colour was it before it fell down the flue?

- thats a good reply

[Emerald Fox]

John V post No.3 - yes, good point. We have one (new) Kidde CO alarm on board but I have just now made a note to buy another. Makes sense.

[Rob@BSSOffice]

Fake Britain (yes I know, daytime TV!) had a thing about fake detectors the other day. They looked ok but didn't meet the requirements for sensitivity and in particular it was mentioned that the sensors get "poisoned" by CO and thus, following a significant escape of CO and some recovery time, the detector may be much less sensitive for a subsequent occurrence. This repeat test being part of the U.K. standard which these fake detectors failed. Some of them just plain didn't work at all.

 

Anyway the point is that detector sensors DO have a limited life and that life is probably further shortened by significant contamination with CO.

 

Moral is to buy from a reputable source (not eBay unless you are sure of the provenance!) and change at or before the expiry date.

 

Fit alarms approved as meeting BS EN 50291-2; these are best suited for boats. Alarms with life-long batteries are available

The CO alarm manufacturer's association - CoGDEM has published a list of alarms produced by its members as suitable for boats.

If you have a Kitemarked alarm, tested to BS EN 50291, or 50291-1, the advice is to keep it, test it routinely and when it needs replacing, choose a unit tested to BS EN 50291-2 (suitable for boats)

 

 

Thank you for the reply - last week in the morning i heard a noise in my log burner in my workshop, i opened the door and a black bird was sitting in the ashes - it must of fallen down the flue in the night - after a few minutes it flew out.

 

One summer we had the cat prowling around our stove. We found no mice, frogs or birds around the base, so I opened the stove door and found a bat. Fortunately I was able to capture it and carry it a few steps out to the patio table where it took a few seconds to recover, before flying off.

[Jim Riley]

 

Fit alarms approved as meeting BS EN 50291-2; these are best suited for boats. Alarms with life-long batteries are available

The CO alarm manufacturer's association - CoGDEM has published a list of alarms produced by its members as suitable for boats.

If you have a Kitemarked alarm, tested to BS EN 50291, or 50291-1, the advice is to keep it, test it routinely and when it needs replacing, choose a unit tested to BS EN 50291-2 (suitable for boats)

 

 

One summer we had the cat prowling around our stove. We found no mice, frogs or birds around the base, so I opened the stove door and found a bat. Fortunately I was able to capture it and carry it a few steps out to the patio table where it took a few seconds to recover, before flying off.

Was it a daft bat?

[MtB]

 

So out in the pouring rain, I got a boat pole and put it down the chimney/ flue, there was a partial blockage towards the top.

 

So where is the material causing the blockage now? I'm imagining it is resting on top of the stove baffle plate and still partially blocking the passage of combustion products up the chimney.

 

The thing about solid fuel stoves peeps don't appreciate is they produce CO in vast quantities. Any gas appliance producing the concentration of CO that is normal for a solid fuel stove would be condemned instantly.

 

A CO level of say, 500ppm (parts per million) would be considered dangerously high for a gas appliance. Even 50ppm would be looked at twice. A Squirrel stove running well is producing so much CO that my professional gas analyser goes off the scale (at 3,000ppm) immediately and shuts itself down to protect the sensor when I stick the collector probe into the space over the coals.

 

Flue spillage from a coal stove is FAR more serious than from a gas appliance.

[bottle]

All cleaned out.

 

Stove running as per normal, will have to open the cratch doors soon, CO alarm showing zero.

[Sea Dog]

So where is the material causing the blockage now? I'm imagining it is resting on top of the stove baffle plate and still partially blocking the passage of combustion products up the chimney.

 

The thing about solid fuel stoves peeps don't appreciate is they produce CO in vast quantities. Any gas appliance producing the concentration of CO that is normal for a solid fuel stove would be condemned instantly.

 

A CO level of say, 500ppm (parts per million) would be considered dangerously high for a gas appliance. Even 50ppm would be looked at twice. A Squirrel stove running well is producing so much CO that my professional gas analyser goes off the scale (at 3,000ppm) immediately and shuts itself down to protect the sensor when I stick the collector probe into the space over the coals.

 

Flue spillage from a coal stove is FAR more serious than from a gas appliance.

Eek!

 

With the door closed, decent rope seal, intact glass and a clean flue this all goes up the chimney, right? I mean we're not hoovering up CO in industrial quantities providing were careful?

 

How about when we open the door to refuel? Is that risky, and there ways we can make that action safer?

[nicknorman]

Eek!

With the door closed, decent rope seal, intact glass and a clean flue this all goes up the chimney, right? I mean we're not hoovering up CO in industrial quantities providing were careful?

How about when we open the door to refuel? Is that risky, and there ways we can make that action safer?

Provided the flue is unblocked the CO will be drawn up the chimney with the door open, or at least most of it will. The problem arises when the natural draw up the flue is impeded.

[bottle]

exactly the problem I had, now after cleaning and checking the smell and CO do not enter the boat when the doors are open.

[Richard T]

In my opinion any boat fitted with a solid fuel stove, gas cooker or any device which has an 'open' flame should be required to have CO and smoke detectors fitted. CO should be in the space where the device is situated and in all sleeping areas.

This may seem to be overkill by some people but it was at this time of year around 20 years ago that I heard via local news that two friends had been found dead in their rented flat - cause of death CO poisoning. The most difficult thing I have ever done in my life was to read at Trevor and Alans funeral which was held a few days before Christmas. Their landlord did take an extended holiday in one of her Majestys secure establishments but this did not bring them back and me and my family miss them to this day - they will never be forgotten.

Anything we can do to prevent deaths from this deadly gas should be done.

[Loafer]

Hear, hear.

 

Just follow all published guidelines and it'll be fine. Don't forget it's NOT lighter than air, nor is it heavier. It mixes with your breathing air at all altitudes within your boat.

 

And it's not CO2.

[dogless]

So where is the material causing the blockage now? I'm imagining it is resting on top of the stove baffle plate and still partially blocking the passage of combustion products up the chimney.

 

The thing about solid fuel stoves peeps don't appreciate is they produce CO in vast quantities. Any gas appliance producing the concentration of CO that is normal for a solid fuel stove would be condemned instantly.

 

A CO level of say, 500ppm (parts per million) would be considered dangerously high for a gas appliance. Even 50ppm would be looked at twice. A Squirrel stove running well is producing so much CO that my professional gas analyser goes off the scale (at 3,000ppm) immediately and shuts itself down to protect the sensor when I stick the collector probe into the space over the coals.

 

Flue spillage from a coal stove is FAR more serious than from a gas appliance.

Why don't I know clever stuff like that.

Wish I was brainy.

Rog

[Jim Riley]

How does wood compare to coal?

[MtB]

Why don't I know clever stuff like that.

Wish I was brainy.

Rog

 

 

So do I...

 

(Wish I was, not you haha!)

[Victor Vectis]

How does wood compare to coal?

I was wondering that too.