Carbon Monoxide Alarm

[Godot]

So...I'm spending the night on the boat, as I do a couple times a week. It is in the lowish 30s. The boat is being heated with a miniature radiator style 700 watt Homebasix heater, which was keeping the temperature only in the low fifties, so I supplemented with a little ceramic Holmes heater which really warms the place up. Electric heat, so I figure I'm OK on the CO generation front.

I have a cockpit enclosure; but it has big areas for ventilation as it attaches to a taffrail that is six inches off the deck. I do have some curtains in the cabin to close off the main area from the galley/navigation area, and from the head in order to contain warmth; but they are several inches off the sole so I would think a fair amount of ventilation would pass from compartment to compartment. The top drop board has about one square foot screened opening protected with a rain shield, not to mention about a one inch gap between the top board and the sliding hatch, so I would have thought there would be enough air exchange. I have no forward vents, so perhaps there is no through venting, although given there is no condensation that I see, to me that suggests the ventilation is working fairly well.

With all that, about ninety minutes ago my Xintex CO alarm went off. I opened the hatches (brrr), and started the fans, and it silenced after about fifteen or twenty minutes.

As far as I can figure, no nearby boats are running any generators or engines. Being a cold weekday morning, this place is practically a ghost town.

I have a very minor headache; but I'm not sure if that is from CO poisoning or from waking up hours before normal. I'm prone to headaches, normally. I don't have any other symptoms that I can associate with CO.

I'm now snuggled in my bunk warming up and wondering what happened. I'm leaving the curtains open to increase the airflow (with the little cube heater the boat should stay warm enough). I'm now a bit paranoid.

[SalientAngle]

I would suspect the CO alarm is defective, unless of course you are in a poor air quality area, which I doubt.

Is the detector older than five years? Has the alarm given false positives in the past?

[s/v Faith]

First,

  You are wise to have installed the alarm.  I have on onboard Faith, and on Emerald Tide.  They can be a little sensitive, but beat the heck out of the alternative.

  John can check me on this, but the alarm can sound for decomposition of a flammable product even without a fire.  The paint on your new heater, or a little dust getting trapped may have been the cause.

  The Kidde combo unit I put on Emerald Tide has a feature they call "hush mode" where you can press a button and it goes silent for a bit....  Keeps me from taking the batteries out when I burn the eggs in the galley.  Any other time it goes off, I investigate just as you did.

[Godot]

The CO detector is just about one year old. It has never gone off before. It does have a silence button; but I was letting it alarm so that I knew when the cabin was clear. I used the new radiator heater for maybe thirty or forty hours (I left it on at home for about twelve hours to burn off the smelly surface oil). The ceramic space heater is several years old. They may be burning something off; but I'm not sure what.

I can't figure out the source of the CO so I am skeptical. Outside of a very minor headache (which I am prone to) I have no CO poisoning symptoms. Still, I have been airing out the boat. I'm still aboard right now, wrapped in blankets, enjoying the cold air. It's time to go to work, though, so I'm expecting to not enjoy the cold air as much when I crawl out of bed.

[Godot]

I just looked at the hatch board and the vent is not one square foot; but closer to 60 square inches. Still a reasonable amount of ventilation, though.

[Tim]

Adam, have you tried just turning the heater off to see if the alarm quits? I certainly would not think that it would be a problem, and am more inclined to think it is a malfunction.

[Godot]

I turned off the heater, but also opened the hatches and started the fans. The alarm silenced after fifteen minutes or so. It hasn't come back on. I just left the hatches open for a long while afterward. The cabin is now buttoned up again and warm. I've been working remotely from the boat, today, which is a good thing as I'm really, really tired.

[Tim]

Seems to me that the alarm should have gone off a lot quicker when opening everything up, I am still guessing it is something else.

[CapnK]

Is this the first time this year you've used either heater? I know mine pick up a good coating of dust during the "off season", and the first use or two burns it off. I think that perhaps the high humidity allows dust and whatnot to stick to & coat the heating elements moreso than if it were staying in a house with filtered, climate controlled air.

Wil be interesting to know the cause, if you find it...

[Godot]

One of the heaters has been in storage for awhile. I have been using the other for a week and a half or so.

Hmmm...

That could be it.