Air your boat to remove gas
I’ve just been reading ‘The boat was steadily filling up with gas that could kill us’ (YM, March 2022). There is a suggestion therein that using a vacuum cleaner to remove potentially explosive gasses is preferable to using a bilge pump.
Clearly there are many types of bilge pump around and whilst the rate at which they could move air is tiny compared to a vacuum cleaner, a benefit to using them is that by design, by and large, the extracted gases passing through said pump type would be separate from the brush gear in the motor, ergo the potential source of an ignition source.
By contrast, the air (gas) which a vacuum cleaner sucks almost without exception after travelling through the dirt filters goes on to flow through the motor (complete with commutator and brush gear) in order to keep it cool which is how something so powerful can be packaged in such a small unit. It’s why the exhaust from vacuum cleaners is so warm; it cools the motor that does all the work. To that end, sucking the potentially explosive gas out with a vacuum cleaner was an accident waiting to happen.
I’m an electrical engineer not a gas engineer, but to me the best solution would be to remove all ignition sources and leave all ventilation ports open. In time, with a decent wind blowing, the explosive gases would get diluted to below their Lower Explosive Limit (LEL) and become safe.
I myself have fallen foul of two batteries getting cooked. One of two house batteries and a thruster battery. They were on the boat when we bought her and seemed fine for a few months before showing signs of heat. My wife thought we’d left the heated blanket on but it was the thruster battery. We replaced both house batteries as if one had been over discharged and failed, the other would not be far behind it. The starter battery was new on purchase of the boat. Dave Brannigan