Heating my Beneteau 31

[Urban_Guy]

We've had a super cold spell here in Vancouver, BC. I was down at the boat running the diesel central heating and after several hours the CO sensor starting going off. Freaked me out so shut heater off and opened all hatches to vent.

Then tried an electric ceramic plug in heater and the same thing happened. I'm concerned as I'd like to try and keep the temperature in the boat above freezing to ward off any freezing issues but not sure if the sensor is accurate.

Has anyone ever had this issue before or know a way to test to see if it's a faulty sensor?

 

[Caboteur]

Why would you have a carbon dioxide (CO2) sensor? This would go off because of too many people breathing in a closed environment? The real killer is carbon monoxide (CO). If it was CO2, you have to ventilate a little. If CO in a closed environment it could also be from the propane stove. Being generally on a mooring I keep the horizontal panel of the companionway open a few centimeters while using the heater or stove. If at a dock with the wind bringing the heater's exhaust fumes back towards the cockpit I would open the center cabin hatch at the first position.
We are getting lows around -20°C, we will heat when the boat goes back in the water in the spring.
Merry Christmas and Happy New Year!
Pierre

 

[Urban_Guy]

Hi Pierre, Happy Holidays to you too! Ouch on the -20 temperatures ... Where on the St. Lawrence are you located? Brockville/Kingston area?
I hope that never happens in Vancouver. I've been here for 25 years and I don't really recall a cold snap like the one we are currently having ... whole point of living on the west coast was for milder weather.
Yes, my bad, it's a CO sensor. Has a green light in the top left and red light on top right of sensor. I'll get a pic and add to this post.
I'm pretty green to all this technology on the boat as my main concern was the danger of CO. I have a friend from Cape Breton who wants to stay on my boat for the month of January and I don't want to go over and find them in a deep sleep to be never wakened.
I was confused why the diesel heat or the ceramic heat would trigger the sensor but after reading some other sites they advised that these sensors are only good for five years. I'll keep searching to see if I can find out why. Maybe the other option is to get a portable sensor and take it over and see what that does.

 

[jssailem]

I had an aged Xantrex FireBoy propane sensor that would shout when I started the engine. Then it would eventually clear and all was well. I spoke with the tech and he aske how old... Not sure. Well you might be due for a new sensor. I chose that route and once installed no repeat of the turn on engine, hear the warning, turn off alarm pattern. Something about the sensor, corrosion, particulate contamination giving false signals.

You might check this on the CO sensor. If a retail not marine grade sensor you may be ready for a replacement.

@Urban_Guy CO carbon monoxide is what is in engine exhaust and can kill you. https://www.cdc.gov/co/faqs.htm

CO2 Carbon Dioxide can also be found in exhaust fumes but it also is what you breath out. Takes a bit more concentration to do damage. https://en.m.wikipedia.org/wiki/Carbon_dioxide

 

[stevemitchell]

If a retail not marine grade sensor you may be ready for a replacement.

I've worked with a number of boaters who have old or non marine grade sensors that go off constantly from random reasons we have yet to understand. I have a Fireboy Xintex model that it appears they don't make anymore - looks like there are some new ones out - http://www.fireboy-xintex.com/

From what I understand, the marine ones do a sample over time and look at the increase in levels of CO, while the residential ones alarm at much lower levels, without a sampling period. This is safer in a house where CO really shouldn't be hanging out randomly, but not so good in a boat. I know that one of my clients had a standard residential one that went off every time another boat passed by in the fairway, and diesel fumes wafted by.

 

[Caboteur]

On your other question, my boat is moored at our cottage. Which is located at the ON, QC, NY junction. Between Cornwall ON and Valleyfield QC. The river widens to about 4Km and forms Lake St-Francis. Kingston is not technically on the St-Lawrence... it officially starts at the St-Lawrence statue just east of the Thousand Islands Bridge. All of this is part of our playground... from there to the Saguenay river and back. It obviously means quite a bit of motoring. I've now sold 32 shares (50%) of my boat to my eldest daughter and her husband. This summer will be the first one of this sharing arrangement.
Pierre

 

[Davidasailor26]

Diesel heating could certainly have caused CO fumes to set off the alarm, but the ceramic heater wouldn't generate any CO at all. My guess is that either the sensor is faulty, or the ceramic heater just stirred up the air, bringing more CO rich air toward the sensor. I would try running the ceramic one again to see if it sets off the sensor. If it does the sensor is likely faulty and should be replaced. In any case there should be no risk of CO poisoning from the ceramic heater.

Disclaimer: ceramic heaters are not without their own threats, mostly from fire. A fire may be started by the heater itself, or by the boat's wiring when it's loaded up from the current draw.

 

[Pizzazz]

Your batteries vent gases when charging that can trigger the CO alarm. In this case, the Ceramic heater just stirred those gases. The easiest way to check is to put your CO alarm above the battery while charging in accept mode. If that is the root cause of your problem just ventilate the battery compartment while charging.

 

[Gunni]

CO alarms have a life limit, consult the manufacturer. Not too expensive, replace. Get a marine certified unit.

 

[Ljuris]

Is your ceramic heater electric or propane fuelled? If it’s propane it can be a source of carbon monoxide.
CO is no joke, no colour no odour, a real silent killer. Get a new detector.