Perfect for medium to heavy seasonal or light residential use, the Centrex 2000 AC/DC allows for both a longer composting cycle, and larger waste volumes than the Centrex 1000 AC/DC. The increased surface area in the evaporation chamber coupled with the larger heating element also provides better evaporation on electric units.
When used seasonally by 7-9 adults, compost will normally only need removing annually each spring. In residential use compost will have to be extracted more frequently.
When used residentially by up to 4 adults, some compost will need to be emptied into the finishing drawer once every few months.
The Centrex 2000 AC/DC features a 370 watt thermostatically controlled heater in a sealed compartment under the unit and the standard Sun-Mar 30 watt turbo fan, with a 2" vent stack to remove the evaporate and fresh odors. This may be used when the unit is in AC operation.
For easy switching between AC and DC mode, the Centrex 2000 AC/DC requires that 2 vent stacks be installed to handle the separate venting functions. The 2" vent is in use when the AC fan is in operation, and the 4" vent is venting the unit passively when there is no power available. As an extra option, we include a 12 Volt 1.4 Watt fan with the Centrex 2000 AC/DC. You may want to install this fan if the unit is to see maximum capacity use, and you should install the 12 Volt fan if you have to put any bends in the 4" vent stack, as you will then lose the "chimney effect" advantage of a vertical stack, and will need to provide air movement with the fan.
You may just install one vent if you only plan on using one function. If, for example, you do not have 110v AC power yet but anticipate getting it in the future, you can install just the 4" vent and leave the 2" vent capped off.
The Centrex 2000 AC/DC is supplied with a 1" drain hose which should be connected to the 1" drain at the bottom of the unit. Click here for more information on handling excess liquid.
The Centrex 2000 AC/DC may be used with one or more Sealand low flush toilets, purchased separately.
The electric EXCEL, COMPACT, CENTREX 2000 A/F and Centrex 3000 A/F will evaporate all liquids, depending on use and climate (ie use over-capacity and extremely humid weather). However, other than the CENTREX 2000 A/F and 3000 A/F, where it is optional, all Central units, the Excel-NE, the Sun-Mar Mobile, and the SPACESAVER should have the overflow security drain connected.
Even though we expect the Excel, Compact, and Centrex 2000/3000 AF to evaporate all liquids in most situations, we always recommend that the overflow drain be connected if the units are being used residentially, or the units will be seeing heavy use for a short period of time (ie party, large family visits). This drain should always be connected as a security measure.
A 10 Foot 1" drain hose and stainless steel hose clamp is supplied with all Central units, non-electric units, the SpaceSaver, and all Sun-Mar Mobile units. Collect and/or treat excess liquid in an approved facility such as a recycling bed, old septic system, holding tank or drain pit.
To make a recycling bed to evaporate and transpirate the liquid without touching the environment, simply dig a bed 18" deep, and line it with plastic sheet. Bed size - normally 3-25 square feet - varies with geographic area and season. Fill it with 6" of gravel then 12" of sand and plant with grass and shrubs. Click here to open and/or download a simple guide to building your own.
Facilities for excess liquid should be installed in accordance with local regulations. In many areas, this is about 1 ft. deep and 2 ft. in diameter. Place sturdy cover (plastic, tin or wood) and a 6" mound of earth over the drain to prevent soil and surface water from settling into the gravel. See the diagram at right.
- - -RecyclingBed
One of the main tasks is the installation of the vent stack, which is included with all units.
The vent kits included in the shipping carton are sufficient for installation in most single story buildings. If more is needed they are normally easy to find. All vent pipes are thinwall PVC.
The drawings illustrate some of the more common vent stack configurations for central system installations:
Detailed Vent Stack Installation Instructions
Electric Unit (2" Diameter) Piping Installation
Piping can be installed up the inside wall; through the wall
at a slight angle and up the outside wall. The choice depends on ease
of installation, visibility, and (especially if the toilet is to be
used consistently through a cold winter), the necessity of insulating
all exposed vent pipe.
Non-Electric Unit (4" Diameter) Piping Installation
Piping can be installed up the inside wall; through the wall
at a slight angle and up the outside wall (with this configuration a 12
volt fan is necessary). The choice depends on ease of installation,
visibility, and (especially if the toilet is to be used consistently
through a cold winter), the necessity of insulating all exposed vent
Leading the Vent Through The Roof (All Units)
As shown in the installation, the vent stack should end about
20” above the peak of the roof so that it is less subject to downdraft.
Where the piping is taken through the roof, the roof flashing provided
may be used to seal the installation or if a new roof is being
installed, the roof flashing should be laid underneath the new roofing
material. DO NOT install horizontal sections of vent pipe to avoid
leading the vent through the roof.
The Diffuser (All Units)
The diffuser provided with the unit is a simple device to be installed at the top of the vent stack with the larger pipe protruding above the smaller. The diffuser design encourages updraft, and discourages wind and weather from going down the vent stack. Unlike wind turbines, diffusers are less likely to freeze up in winter, and are more effective in calm weather.
Sun-Mar units serve as a reliable year-round facility when prepared for continuous or periodic use during the cold winter months. All units are made of fiberglass and marine grade stainless steel; so even if the compost freezes in the drum, sub-zero temperatures will cause no damage.
Winterizing Your Sealand Toilet
While the composting system will not suffer any damage due to freezing, a particular part on the Sealand low flush toilet will. This part is the water valve. You will of course not need to do this if you are keeping the bathroom heated throughout the winter. For best results, do one of the following:
What is the 12 Volt Fan?
The 12 Volt Fan is meant to accelerate airflow in all
non-electric units. It comes pre-installed in an 11" piece of 4"
diameter vent pipe so that it will fit inline in your vent stack. It
also protects against downdraft and increases the evaporative
performance of your non-electric unit by about 10 to 15% (still not
enough to evaporate all liquids on an NE).
In Which Situations would I need a 12 Volt Fan?
How Do I Install the 12 Volt Fan?
Choose a section of your vent where you will easily be able to
access the fan, and connect it to the battery. Cut a suitably sized
section of vent stack and insert the fan into the stack, ensuring that
the piece is positioned correctly so that the fan is blowing upwards
(coupling will be at the bottom). Caulk both seams with silicone for
the best airflow.
How Do I Power the Fan?
With DC Power:
Purchase a solar panel appropriate to the wattage of your fan (5 Watt for the 1.4 watt fan, 10 watts or above for the 2.4 watt fan). You will also require a 12 Volt battery (Sun-Mar suggests a deep cycle marine battery for best results). Connect the wires on the fan (red wire positive, blue negative) to the appropriate terminals on the battery, and the appropriate wires on the solar panel to the battery. The battery will store the charge from the solar panel, ensuring continuous operation of the fan even at night or cloudy days.
With AC Power:
Purchase a 12 Volt AC Adapter from any electronics store. Cut
off the female plug. Attach the positive wire to the red wire, the
negative wire to the blue wire, and secure both with small wire
connectors (marrettes). Plug into wall.
12 Volt 2.4 Watt Fan
This fan increases the airflow level and is necessary for
situations where there may be competing drafts, which is true in the
case of the AF NE models and the AC/DC, dual-vented models.