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Q&A Blowers & gensets

Q: Should I run the blowers all night when I run my generator for air conditioning while anchored?

Q: Should I run the blowers all night when I run my generator for air conditioning while anchored?

A: Unless your boat and equipment were specifically designed, built and maintained for this purpose and to all relevant standards, you shouldn’t run your generator at night while you’re sleeping. A generator involves a combination of an internal combustion engine and the production of electricity. That alone should be warning of potential problems.

You’ve got arcing (though it’s supposed to be controlled), you’ve got combustion (though it’s supposed to be internal), and if you’ve got a gas genset you’ve got a highly explosive fuel. Even with a diesel generator, there’s a reasonable possibility of sudden conflagration should a pinhole leak develop in one of the high-pressure pipes running from the injector pump to an injector. The resulting vapor could be ignited by a source of high heat or from sparks.

However, there are additional potential problems. One significant concern is that of carbon monoxide and/or other gases from the exhaust. Even a small leak in the system can prove fatal inside the boat. And although exhaust is emitted outside the hull, it can find its way back into the boat. High-quality generators and proper, careful installation and maintenance can reduce these risks substantially, but they are still there. Things can go wrong no matter how careful and thorough you are, and we’re talking about your life.

Modern, quality generators have many safety/protective devices to lessen the risks, such as alarms for high exhaust temperature, high coolant temperature, voltage and/or amperage fluctuation or values beyond parameters of safe operation, and other indications of trouble. But will these alarms work and will you hear them while you’re asleep, with the background noise of the air conditioning and the generator?

Also, your boat should be equipped with fully functioning and well-

maintained smoke and carbon monoxide alarms. If they are functioning well, you probably will hear these, but people sometimes disarm them because they go off while cooking or when the battery is weak.

So as for running the generator and AC at night while you sleep, don’t do it. Open the hatches. Get good, low-

amperage 12-volt fans, and let them cool you. There are some great ones on the market. Perhaps a wind chute would work well with your hatch, particularly if you’re sleeping in the bow. And you may grow to love smelling salt air during the night, along with the sound of the wind and waves lapping on the hull.

As for the blower, boats usually are equipped with them to void explosive fumes when you start the engine. They usually are designed to run for short periods of time, not continuously for long periods. When you run such a blower continuously for a long time the motor may overheat, seize up and die or, much worse, cause a fire. This isn’t good at any time, and it’s especially bad if you’re asleep.

If you do run a generator at night when you’re asleep (and I hope you don’t) it would be a good idea to run blowers that are specifically designed, installed and built for this purpose and to all relevant standards. Be sure that no air is being sucked into the boat in a manner that could allow introduction of exhaust gases. But the safe thing to do is to turn off that generator overnight at anchor and enjoy the fact that you’re on a boat.

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