Fire Alarm

"The Owner suspects his deceased Grandfather"

Sounds like a reasonable guess.

To not upset the other boats, if you drill a little hole either side of the reset button and put a splitpin through, at least you will get some sleep.

(I never said that)

Alarm

While we are on the subject of alarms/biongs/bleeps/klaxtons.

Does anyone listen to them???????????

I'm sorry but everytime I open a car door, do I need a Beep-Beep to tell me I've just opened a car door? I sit in the seat, Bong Bong, yes I know, SHUT UP. Give me 2 seconds to put the belt on.

After a while all these beeps and flashing lights make us immune to them.

I used to wake up when pumps went off at night or something sounded 'funny'.

Having a fridge alarm go off while you're standing in it still baffles me,what do you want me to do? Lock myself in???? Thats just a 2C degree drop, not the Moon plummetting.

Ok, in the Engineroom a flashing light is needed when you've got ear defenders on but 99% of the time its all B/S.

What you want is a big RED flashing light and a klaxon shouting "This is going to hurt" at you.

Then, and only then, do these bloody Beep Beeps make sense.

Rant over.

Take a shower and stop breathing. It could also be outgassing from the carpets, veneers, glues, etc.Many of these units just get too darned sensative. Once you confirm that there is no problem hit the reset. If it continues open it up and disconnect the wire. Often if they're disconnected for a while they're ok again. Otherwise replace the unit.

First, I don't know a thing about your boat or it' detection system. I'm a ME/EE.

What I can tell you for certainty is CO is a product of INCOMPLETE Combustion.
usually not enough air (O2)to complete the combustion with a Hydrocarbon. Also Hot smoldering soot can release CO. In the States OSHA limits worker to 50 ppm. You start getting 400 to 600 ppm your going to feel symptoms and need to leave the area. The thing about CO is it accumulates,a source putting off 5 ppm to 20 ppm (a properly adjusted gas stove) is really no threat for 1 hour,but 20 hours of use latter your exposed to 400 ppm.

Places that burn hydrocarbons are always the fault,(unless you have a leaking bottle of CO on board for calibration reasons.) Engine, gen sets,etc. A yellow flame is a signature of incomplete combustion.............Gas stoves ,ovens are big producer as are propane vented or un-vented Fireplaces. They lower the O2 to get the life like yellow flame look.

CO analyzers you buy in most store add up the ppm until it's gets to a preset trigger point. You need a CO analyzer(direct reading) & possible a combustion analyzer to track down the source. In the states Bacharach inc. make some of the best. You can even have them provide a NIST traceable certificate in you want. I'm pretty certian different yachting societies will have different standards

In the states ASME (American society ofMechanical engineers),or a member of ASHRAE (American society of heating,refrigeration & air conditioning), or even RSES (Refrigeration service engineers society) should have the proper tools & knowledge to track down your CO problem .

Of course take this serious from the start,if it's a false alarm,let the experts prove it. It's very possible you just grill to many Steaks without proper ventilation.

Do you have a fresh air make up system that sucks in air from out side? That might also be sucking in exhaust from a gen next door? Or even yours at anchor?

Fish,

It is obvious you are not an natural engineer- You should always push the reset button in first and use the split pin to hold it in or it will not be able to be reset with a split pin all the way through it - Will it.

I find a toothpick or matchstick often works quite well. Sometimes followed by the float test.