Carbon Monoxide Detectors

[Mackaroni]

This is my first post here, but I have been lurking for quite a few years. I now own an O'day 302 and am looking for advice in complying with some of the recommendations from the survey.

It calls for installing carbon monoxide detectors and smoke alarms on the boat as there are none. I plan on installing at least one CO2 detector in each of the private sleeping areas and maybe one in the saloon area as well. My question:

In installing these, do you normally hardwire these, and if so, what circuits should they be installed on?

Thanks

[nigel1]

Easiest way would be battery operated detectors, least, thats what I fitted.

[CaptTom]

They are wired in on new boats. Sometimes directly to the battery so they can't be turned off (dumb idea in climates where boats are in storage half the year.)

One key point: don't buy home CO alarms. They will give more false alarms.

[ravinracin]

CaptTom, can you explain why one should not be using a home type CO detector? I have installed both CO and fire alarm home type alarms on my boat and haven't had any false alarms. thanks.

[TacomaSailor]

I've used a Kidde home CO / Smoke detector on our boat since 2006. It gives no false alarms for CO and does provide an alarm when I intentionally introduce CO into the cabin.

Way back when there was a very long and heated discussion about why a home CO detector was not appropriate on a boat but I never did understand why it is not.

[CaptTom]

I found this out the hard way. I got false alarms from a "home" CO detector. By false I mean at the dock, with no engines running or fuel burning in anything. This was late winter; perhaps the temperature was part of the problem. It happened a couple of times after I first entered the boat, so maybe it was condensation from breathing.

Also, as I understand it, marine versions use an average CO level over a longer time, and won't alarm on a momentary spike. I'm not an expert, just repeating my interpretation of what I heard.

[MarkJ]

I have a battery operated smoke detector and it just sits on a shelf. When my cooking is crap i can just throw it in the forward cabin till everyone has pood poisoning

[hellosailor]

Tom your decision is based on one detector. Which simply could have been a lemon.

In the last few years there have been changes in detectors and more importantly, new information being pushed out. A cheap ionization type smoke detector dies in 5-7 years, they do not last forever. Apparently airborne dirt clogs the detector grid at that point. So manufacturers are now offering detectors with a built-in 5-7 year battery, and when it says "Replace" that means toss the whole thing out and replace it, not just the battery. Since they cost about the same thing and you'll only hear the midnight chirp of "feed me!" once every six years or so, that makes sense to me.

You can also get these combined with a CO detector--and since they also die as they age...still makes good sense.

But I've personally seen a number of ionization detectors simply NBOT GO OFF while there was obvious smoke in the room. Some from aging, others because the ionization detectors take about 30 seconds longer than the photocell ones to trigger. If you've ever watched a fire grow, that's critical time. And the photocell detectors don't quietly die in five years like the ionization ones do.

So bottom line? Avoid the $10 detectors, try to find something better ($35-50) and shop around. There's apparently a huge markup and a huge variation in selling prices, and some of the new combined units are being sold for way less than the price of the old separate ones.

For any of them, I'd "marinize" them by putting some silicone grease on the battery contacts, but I do that for anything with electrical contacts in salt air.

[CaptTom]

Thanks, agreed that a sample size of one isn't significant, and the info I read was some years ago. No doubt the technology has changed.

I'll avoid the cheap-o units when I go shopping for a new one in the spring. The sealed battery makes sense. Too bad the new ones don't fit in the same screw holes as the old ones!

Interestingly, the CO alarm at home started chirping a few weeks ago too. Turns out it had a pre-programmed 10-year life span.

[hellosailor]

The Nooze Media keep making their annual pitches for "change your batteries when you set your clocks" twice a year, but they still haven't read any of the press releases that have been saying "Throw out your detector!" for the past five or ten years.

Remember, if you have an ionization detector onboard, you shouldn't try sailing into Japan. You're carrying radioactive material. (VBG)

[glenn.225]

Originally Posted by hellosailor

Remember, if you have an ionization detector onboard, you shouldn't try sailing into Japan. You're carrying radioactive material. (VBG)

Yes you may tip the balance with what is already there.

[RainDog]

We have been using the Kidde for 4-5 years now and it still works great. I was shocked how quickly CO rises when I first got it. For sure an eye opener. I quickly learned exactly how much I need to vent when cooking to keep it near 0.

[Reliant37]

Is it worth the money to buy the FireBoy XINTEX CO detector Model CMD-4MR? This is supposed to be rated for Marine use. Does anyone have experience with this model? Going to use in 37 foot sailboat with installed generator. Signed, rag bagger

[GordMay]

Greetings and welcome aboard the CF, Rag Bagger.

[hellosailor]

According to Xintex "It features automatic generator shutdown capability. " and that's important IF you have a generator that might be killing you. But a total waste of money if you don't plan to use it that way. Normal CO detectors will just alarm, without shutting down anything.

Remember that a CO detector is perishable, like fruit on the shelf it has a shelf life and must be replaced every so often. More important to replace them on schedule.