Five Types Of Marine Heads
For most vessels there are four distinct types of marine heads. Each with a different method of flushing away the waste. These are the common types of boat heads:
- Porta-Potty (Portable Boat Toilet)*
- Manual Pump Head
- Electric Head
- Vacuflush Head
- Composting Marine Toilet
* In some jurisdictions, for power boats a Porta-Potty doesn’t qualify as a marine head.
A Porta-Potty, sometimes called a cassette toilet is the most basic head installation to deal with onboard sewage. This type is common for smaller vessels that don’t have the space for a full sanitation system. It has both a refillable water supply and holding tank incorporated into the actual head. There is no permanent plumbing system in a portable toilet system, the head does all the work with a caveat.
To operate it, you do your business, then actuate a hand/foot-operated pump. This both pumps water into the bowl and opens a trap door system that lets waste fall into the lower holding tank.
Advantages for this type are the space it saves, it’s near impossible to clog and the low initial cost. Plus if you add a chemical deodorizer to the holding tank, it’s virtually odorless.
The caveat for a portable toilet is when the holding tank is full. It’s not an enjoyable experience to have to remove the tank on shore and dump the holding tank.
Manual Pump Head
The manual pump head abandons portability as it uses a permanent plumbing system. This type of head uses a pump, hoses, valves and a larger holding tank to store waste. I’ll further explain waste storage options later in the article. Using an installed holding tank means you need to empty waste at a marina’s pump-out facility. This is more civilized than hand emptying a Porta-Potty tank.
A manual pump head like a Jabsco, consists of the bowl, a hand-pumped raw-water intake, and a discharge hose. The output hose flows to the holding tank, then flows to either a pump-out hose or self-discharge hose. Depending on your waste storage system, there might be a macerator too. This chops up waste to smaller bits to reduce clogs in the waste hoses.
To use it, once you make a deposit, you move the pump up and down by hand around a half dozen times. On the up stroke of the hand pump, the system draws water into the bowl. Next, on the down stroke the system pushes the waste out through the discharge hose.
The big advantages of this head is that it’s repairable, easy to maintain and quiet to use. Another great function of this type of head is the ability to switch to either wet or dry flushes. A dry flush is when you set the switch to not allow fresh water to enter while pumping. Dry flushing is for fluid only waste, to help reduce the volume of liquid filling the waste holding tank. Which is a genuine concern for boats with a small holding tank on board.
Shopping Considerations For A Manual Marine Head
- Direction Of Pump Handle Throw. A horizontal throw (back and forth) tends to be less tiring than a vertical throw (up and down). Expect horizontal throw pump handles to cost more than vertical throw versions.
- Seat Height & Sturdiness. Ensure the height of the seat is at a comfortable height for yourself. Next pay attention to the material durability of the seat and its hardware. Using the head in rough waters puts stress on the seat hinges. So look for beefy hardware that won’t snap and dump you off the seat before you finish.
- Larger Joker Valve. This rubber valve is what the waste passes through during each hand throw of the pump lever. A bigger valve size means a lower chance of clogging. Bear in mind, a faulty joker valve can permit water leakage into the sink in rough water. Keep a close eye on the component.
- Ability To Rebuild Toilet. Marine toilets tend to need rebuilding every couple of years depending on amount of use. Look for brands that offer quality rebuild kits and instructions.
- Toilet Weight. If you are upgrading from a Porta-potty it’s important to know that a manual head will add about 22 pounds (9.98 kg) of weight.
An electric head is an improvement of a manual head because it replaces the need to hand pump the flush. You either replace the manual head with and electric model or upgrade the existing head. To do so you need to add an electric pump, flush switch and a 12 volt circuit to the compatible system.
This design uses an electric pump to create suction to pull in water and push waste out from the bowl. Inside the pump contains a macerating function that grinds up waste and paper. Which reduces clogging of the output hose to the holding tank or overboard, if you are offshore.
Power consumption of an electric head is low due to the quick speed of the flush, as most finish in under 30 seconds. Yet, the toilet will use a brief load burst of between 20 and 30 amps. Thus, you should consider adding a separate circuit breaker for an electric head.
To operate this type, a user only has to engage a button for the duration of the flush. For guests that aren’t used to marine sanitation this type of boat toilet is great.
Keep in mind that this design is quite noisy during a flush. Due to the sounds from the electric macerator and pump. So night flushes may annoy guests sleeping next to the bathroom. Another consideration when shopping for this type of head is access to the moving parts. This head does need maintenance, if the moving parts aren’t accessible expect headaches. The biggest issue though, is if the boat losses power the toilet pump motor losses flush function.
What is a Vacuflush head? As it’s name suggests, a Vacuflush uses an electric vacuum pump to keep a constant vacuum on the waste line. It uses a freshwater input to cut odor and calcification build-up in hoses. Calcification can happen due to lake and seawater organisms that die in the hoses. This head also uses very little water for operation compared to the 3/4 gallon the manual or electric heads use. Plus it uses much less power consumption at 3-7 amps whereas electric uses about 10-15 amps.
How Does A Vacuflush System Work?
1. Vacuum is constant in the system at all times. Before sitting down, you need to add water in the bowl. Most need you to raise the foot pedal or lever to do this.
2. Sit down and do your business. You flush by pressing down on the pedal/lever. This will release the vacuum pressure stored by the system. This change in pressure inside the vacuum tank activates the vacuum pump. Resulting in the bowl clearing in an instant moving waste through the vacuum pump. Pushing it at high speed through the output pipes to the holding tank.
3. Once you release the flush pedal/lever, you recreate a vacuum tight seal. The vacuum pump continues to run (its noisy) until recharging the vacuum level in the system. Recharging takes about one minute, depending on how long you held the flush.
A Vacuflush marine head is typical for larger power yachts for many years. They work well but are very expensive to retro fit and repair compared to the other types.
The composting head is a bit of a newcomer to the marine-toilet market. Two important install considerations for this type are the footprint and bulkhead clearances. If you have the room though with this type there are no hoses or holding tank need either.
Another benefit over other systems is it doesn’t need seacocks or through-hulls. The waste system works by separating the solid and liquid waste. Inside it channels liquid waste into a single tank and solids into a composting tank. In a typical design there are two small holes in the front of the bowl for liquids. Then a large center hole for solids. Both tanks sit under the head to save space in the hull, which is the other big bonus of this style of boat toilet.
To use this type of head it’s best to do your liquid or solid business sitting down. Expelling liquids sitting down is to ensure you hit the small liquid only holes. For solids activate the handle on the side to open the flapper to the compost bin. After you finish, close the flapper to seal the compost bin. Next turn the big crank handle a few times to mix the compost medium and the solids. An integral vent fan keeps the compost dry and helps to quicken the process.
Although boaters do feel a composting head is a bit of a learning curve, when set up and maintained its odor free. Plus you’ll never have to worry about clogged hoses, finding or paying for pump out stations again. There are almost no moving parts, almost nothing that could break, and next to no maintenance. You just need to clean it. The downside is you will have to come close to your waste during disposal but that’s not a bad trade off.