I use a couple of the home units, the only "false" alarms I have gotten, are from charging
, (apparently the sensors are also sensitive to Hydrogen). I would not neccessarily call that a disadvantage, as I don't want hydrogen build up in cabin
I would not call them beeping over a spike caused by a passing power boat
a "false" alarm
either, as they are rightly informing you of CO, even if not dangerous levels for short term exposure.
It is very likely that they will become less sensitive in time, as the other gas detectors I have used in an industrial enviroment also lose effectiveness. Just replace them every few years, as the new ones are better anyway.
Other than being built for 12v power, and lower sensitivity, I see no reason for the marine
units to cost 10 times as much as the home units. If you have a big expensive boat make your own decision, but I decided that a "cheap" unit is better than no unit.
As far as Diesels making less CO than gas engines, less is not equal to zero.
Diesel (compression ignition) engines run with an excess of air and often produce less than 1200 ppm CO. When diesel fuel is burned incompletely or when overloaded and over-fueled (rich mixture), diesel engines will produce high concentrations of CO
CO emitted from the tailpipe of engines burning gasoline, 10,000-60,000 parts per million (ppm)
Dept of Agriculture.
1200 PPM is considered dangerous, Even a finely tuned diesel producing "only" 200PPM will eventually cause problems in an enclosed enviroment.