The Excel NE has no fan or heater. Odorless operation is achieved by a 4" vent mounted at the top rear of the unit which acts like a chimney on a wood stove. For good air movement the vent should be installed vertically and to 2-3 feet above the peak of the roof.
The optional 12V fan should be installed if you need to install the toilet with any bends in the vent. No more than 2 45° bends are encouraged, even with the fan.
If the Excel NE is used residentially or heavily, or is in a place which is subject to downdraft, the optional 12V fan should be installed in the vent stack. This fan draws 1.4 watts and can be powered by a solar panel and 12 volt marine battery.
The Excel has enough capacity that it can be used just about anywhere; in residences, cottages,
pool houses, boats, and even in light commercial applications. The chemical make-up of the waste is completely changed by the time it reaches the finished compost stage, and the finishing drawer isolates the compost from odor and contamination. The 4" vent is attached at the top back of the Excel and can be installed invisibly by running it through the wall and up the outside wall. For comfort the Excel has a sturdy detachable footrest which can be removed to pull out the finishing drawer.
To simulate residential use the Excel was tested by the National Sanitation Foundation (NSF) at maximum capacity for 6 continuous months, during which the Excel produced no odor and produced a clean, safe compost. Only Sun-Mar self-contained units are listed for residential and cottage use by NSF, whose Standard #41 is the toughest composting performance standard in the world.
Every Sun-Mar unit comes with:
- An owner's manual
- Warranty card (25 years on the fiberglass shell and 3 years on all other parts)
- Peat mix (30L bag) for starting off the unit
- Rake for periodic clearing of the evaporating chamber
- "Compost Quick" enzyme for speeding up composting
- "Microbe Mix" bacteria for inoculating waste
How It Works:
Every living organism consumes nutrients and creates waste. The bacteria complete this cycle by taking our waste and converting it into safe compost for our plants through the processes of decomposition and evaporation. That's why Sun-Mar toilets are designed not only to harness these natural processes, but to optimize and accelerate them. Toilet waste is over 90% water content. This can be evaporated and carried back to the atmosphere through the vent system. The small amount of remaining material is recycled into a useful fertilizing soil.
Four things are needed by the bacteria in order to turn waste material into compost: fresh oxygen flow, moisture, heat, and organic material. Air is being drawn in either by a fan (or on non-electric units by the vent chimney) over the evaporating chamber and up the vent stack. Not only does this evaporate excess liquid, but by continuously pulling air in we ensure no smell escapes from the unit. Moisture is obtained directly from the waste. Evaporation is assisted on electric units by a thermostatically controlled heater in a sealed compartment underneath the evaporating chamber. The organic material is best supplied with a bag of Compost Sure, which is a mixture of coarse peat moss and chopped hemp stalk, designed to maintain porosity and hold oxygen and moisture in the compost while supplying it with the carbon it needs.
Use and Maintenance:
Operating a Sun-Mar is easy, use it just like a regular toilet. Toilet paper needs no special treatment as it is easily decomposed. There are only two things that you have to do: Add some bulking material regularly and turn the handle to rotate the drum every few days. To remove the compost (this is normally done annually), release the lock and rotate the drum backwards
Everything you need for installation and start-up is in the box, merely plug it into a regular 3-pin plug and assemble the vent stack. Then just add half of the 8 gallon bag of Compost-Sure and half the Microbe Mix bacteria pouch to the Bio-Drum. Your toilet is then ready for use!
Frequently Asked Questions:
How much odor comes from a Sun-Mar composting toilet? None. Air being continuously drawn into the unit and up the vent stack, creating a partial vacuum inside the unit. In addition, the composting drum fosters a good aerobic compost which produces no odors.
How often do you have to empty it? Never completely empty the unit. You typically empty some of the compost out of the drum once per year. In cases of continuous use, you may extract some compost more often.
Do I add any chemicals? No. The only thing that is added is a bulking material which is a combination of coarse peat moss and hemp chips, (50% peat moss, 50% hemp chips). Chemicals are, in fact, dangerous to the composting process and should never be added at all.
How do you clean the unit? You only have to clean the bowl (in a central system) or bowl liner (self-contained unit) as you would a regular bowl, except without the use of chemicals. Recommended cleaners are Sun-Mar Compost Quick or hot water that is mixed with baking soda or vinegar.
What if electricity is not available? No problem! Each Sun-Mar toilet is also available in a non-electric version.
I have a generator that runs part of the time, can I use an electric unit? No. A non-electric unit is recommended or a unit that has both electric and non-electric capabilities (AC/DC unit).
What happens in the winter? Nothing. The compost remains in the drum and freezes, so not composting is taking place. The elements will NOT damage the system during the winter months. If you are planning to use the unit for only one weekend per month in winter, it will suffice as a holding tank.
Can a Sun-Mar composting toilet be used all winter long? Yes. If the area where the composting toilet unit is heated to a minimum of 55 degrees Fahrenheit (15 degrees Celsius) throughout the winter, then composting will occur. Because composting is a biological process, temperature is always a factor. The community of bacteria living within the composting drum have an optimal survival temperature just like any other living creature, and cannot compost efficiently below 55 degrees Fahrenheit. Conversely, these bacteria will compost faster at higher temperatures.
