Dometic MasterFlush 8740 Electric Macerating Marine Toilet

The Dometic MasterFlush 8740 brings the comfort of a home bathroom to your boat. It's a permanent, standard-height electric toilet built around Dometic's MasterFlush macerating system, which grinds and pumps waste in a single push-button cycle. Because the macerator does the heavy lifting, the 8740 doesn't need to sit directly over the holding tank. You can mount it wherever the layout of your head compartment makes the most sense and route the discharge line to a tank somewhere else on the vessel.

Comfort was clearly the goal here. The bowl is full-size ceramic with an elongated shape and a seat height of about 19 inches, which is very close to what you'd find in a residential bathroom. If you've ever stepped off a boat with a cramped, low household toilet and wished for something more familiar, this is the piece that fixes it. The glazed ceramic surface wipes clean easily and resists staining and odor far better than plastic bowls, so the head stays fresh through a long weekend or a full season of use.

The macerating action is the real story. Inside the base, an electric pump with a stainless steel cutting blade reduces waste and paper to a slurry before moving it out through the discharge line. That means smaller-diameter plumbing, longer runs, and fewer clogs than a gravity or manual toilet can manage. It also gives you flexibility to install the head above, below, or well away from the tank. Two flush modes let you choose how much water each cycle uses. A normal flush clears the bowl completely, while a low flush conserves fresh water when you're watching tank capacity on a longer trip.

The 8740 draws fresh water for flushing, which keeps sea-water odor and marine growth out of the bowl and the plumbing. It runs on a standard 12-volt DC supply, so it ties straight into your boat's house battery system without an inverter or separate power source. Operation couldn't be simpler. You press the flush control, the toilet adds water, macerates, and pumps in one smooth cycle, then refills the bowl and shuts off. There's no pumping a handle and no guessing whether the bowl is truly clear.

Installation follows familiar Dometic conventions. The footprint measures roughly 14-3/4 inches wide by 21-1/2 inches deep, so it drops into most existing head compartments, and the standard fresh-water and discharge fittings make it a sensible upgrade from an older manual or gravity unit. If you're replacing a tired toilet that clogs, smells, or takes a dozen hand pumps to clear, moving to the MasterFlush 8740 is a noticeable step up in daily comfort.

This is a toilet you'll appreciate most on the water, when guests are aboard and you want the head to just work. It's quiet enough not to wake the whole cabin, efficient enough to protect your fresh-water supply, and built by a company that has focused on onboard sanitation since 1960. Dometic engineers these systems alongside boat builders, so the fit, the fittings, and the long-term reliability all reflect real marine use rather than a repurposed household design.

A few practical notes help you get the most from it. Size your discharge line and holding tank to match the pump's output, keep the fresh-water supply clean, and run the toilet regularly so seals stay conditioned during downtime. Because it's a permanent unit rather than a portable one, plan the plumbing and the 12-volt wiring as part of a proper install, ideally on a dedicated circuit with an appropriately rated breaker. Done right, the payoff is a head that stays quiet, clears fully every time, and asks very little of you across seasons of use. It's the kind of upgrade guests notice the first time they use it.

For a permanent installation where you want dependable, push-button convenience and a genuinely comfortable seat, the MasterFlush 8740 is a strong choice. Pair it with a properly sized holding tank and the correct discharge plumbing and you've got a marine head that behaves like the one at home.