carbon monoxide detector "Safe T Alert" problems

[Al9586]

Over the last week we have started to experience trouble with our hard wired, dealer installed CO detectors. And as it would have it about 9 pm just after settling in, the one in the aft sleeping cabin went off. We ventillated the boat, checked outside, put a fan on the detector and it alarmed for an hour before returning to normal. Two nights later it did the same thing...I ended up cutting the power after almost 2 hours. The other two units did not alarm. We had not been cooking, running the engine, and there had been no activity to our knowledge in the marina that would explain the cause. There is more action during the day and we never had an alarm during the day - as luck would have it only at night when we are trying to sleep. We bought a 9-volt powered unit to replace the disabled detector and it has given no warnings in the meantime. NOW, just last night, the detector in the saloon did the same thing, going off at 9:45 pm. Rather than fool around with it, I cut it immediately. It seems that I had read a message or two in the past about this, but asking the archives for co detector did not pay off. I'd like to hear if anyone has had a similar problem and what you did to take care of it. Did you get any satisfaction out of the manufacturer?

 

[Bill Bell]

Battery Gassing?

We had problems with the CO detector going off all the time. I normally left it disconnected. I sent the unit in for repair (they replaced the unit). Same problems. This year I replaced the two wet cell 4D batteries with AGM and the problem went away. My batteries always were putting out enough vapors or gas to set the CO detector off. Maybe you have something similar.Bill

 

[Al9586]

Don't think that's it...

Thanks for the input Bill - battery charging was not something I thought about. But, our four group 27's are located in boxes in a lazarette in the cockpit, and I doubt that was it, but this is something to investigate. No heavy battery charging was going on (except perhaps full charge maintenance),but the real deal closer was that the replacement CO monitor was closer to the batteries than the saloon monitor and it was silent. I still think that two of the three monitors have actually failed - perhaps jinxing myself for the remaining sensor to fail sometime after we go to sleep tonight. I wrote the manufacturer and they suggested swapping the alarming unit with one that was not sounding an alarm. I will try that this weekend and see what happens.