A BRIEF HISTORY OF THE "SUN-MAR" COMPOSTING TOILET
It's as simple as 1-2-3
Back in the 60's Hardy Sundberg (Father of the present Sun-Mar
partners) was trying to work out the best toilet set up for his
cottage in Sweden. He started with an incinerating design,
before finally concluding that maybe all he had to do was to
help nature do it's own thing. The idea of a composting toilet
Hardy put together all kinds of toilets, before he
hit upon his gold medal design. The basic problem was, and still
is, how do you optimize conditions for breaking down what we at
Sun-Mar call "solid material," while ending up with a safe compost,
evaporating the liquid, and producing no smell. The
key turned out to be a composting drum. A place where you
could keep the compost moist; retain the heat in the core
of the compost, and achieve perfect mixing and aeration
simply by rotating and tumbling the compost. Nothing too
clever there you may say.
Sure, but Hardy still had to work out
a few other pieces to the puzzle. How to make sure the compost didn't
get too wet; how to make sure the waste went into the
drum and stayed there; and how to extract compost from
the drum. Hardy's solutions were pretty simple (some would say elegant).
He cut a hole in the drum to receive the waste, and fitted a swinging
door which closed automatically as the drum rotated for mixing,
and opened automatically when rotated backwards for emptying. He
put a screen at the rear of the drum to drain any excess liquid
directly into an evaporating chamber. Finally he came up with the
idea of a stopper which maintained the drum in a top dead center
position to receive the waste, and allowed the drum to rotate backwards
only when compost was being extracted.
The rest was much easier;
He placed the second chamber, the compost finishing drawer,
immediately below the door in the composting drum. That way compost
falling directly into the drawer could be left in the drawer for
completion of the composting process, and emptied only when more
compost had to be extracted from the drum. Compost in this second
chamber was isolated from liquid and surrounded by
a stream of drying air. The evaporating chamber, the
floor of the toilet, formed the third chamber, from where
excess liquids not absorbed by the compost were evaporated. Hardy
did this by pulling air through intake holes at the front of each
side of the toilet, over the evaporating chamber, and up the vent
stack. By so doing, he created a partial vacuum inside the
toilet to ensure that there could be no smell under any circumstances.
In 1979, for Hardy Sundberg, the whole concept came together as
easy as 1-2-3-.
It was so good we've spent the last thirteen years polishing
"SUN-MAR" is the first and only self contained composting toilet
in the world to be
NSF Listed in Standard 41 - Sun-Mar Excel - 89
tested and certified by N.S.F. (The National
Electrical Features are CSA APPROVED LR 55925
Our founder's first composting toilet received
a gold medal at
the International Inventor's Exhibition in Geneva, Switzerland.
A QUARTER CENTURY OF TECHNICAL LEADERSHIP
The HISTORY of "SUN-MAR" closely parallels the development
of cottage toilets over the last 37 years.
Our first cottage toilet (an incinerating design)
was invented in Sweden.
Abandoning incineration due to the high energy requirements,
the first self contained composting toilet was developed
in Switzerland by the Father of two SUN-MAR partners.
Rights to the original composting toilet were sold, and the
"TROPIC", a new design incorporation several improvements,
was first produced in Sweden. (The rights to this unit were also sold when our superior technology outstipped its usefulness).
Production moved to North America, and the WCM, the
first central composting unit, was produced.
First three chamber self contained toilet was introduced
using a Bio-drum. (The forerunner of today's EXCEL
Bio-drum design proved so successful that a non- electric
version (the EXCEL N.E.) was introduced.
Non electric version of the WCM central composting
unit (now known as the CENTREX N.E.) was added to the line.
The SUN-MAR EXCEL became the first composting toilet
to pass the long term composting tests of the National
First dual vented unit (the EXCEL AD/DC) was
marketed for those with a non continuous 110 Volt supply.
SUN-MAR introduced the "COMPACT", a lower profile,
more rounded unit with a patented variable diameter Bio- drum.
The "CENTREX" family of lower profile, front vented
central units was launched.
The "ECOLET", the first self contained composting
toilet ever designed for Marine and RV markets, was introduced
THE BEST JUST GOT 56% BETTER!
Each year we have made small quality and performance improvements.
Not so in 1994. There are no less than four significant
improvements built into 1994 units, including a massive
56% increase in composting capacity.
Bio-drum Capacity up by 56%
As most of out dealers and users know, the secret to "SUN-MAR's"
superior composting performance lies in the composing drum, -
the Bio=drum. For the last 14 years, the tumbling action
of this Bio-drum has allowed "Sun-Mar" to optimize composting
performance by keeping the compost moist, oxygenated, mixed
and warm. Now "SUN-MAR" engineers have found a way
to increase usable Bio- drum capacity by an incredible
56% without increasing the size of the toilets!
Sounds impossible? Here's how they did it. First, the drum was
extended closer to both the front and back of the unit. Then,
by relocating the drum lock mechanism they increased the diameter
of the Bio-drum. Taken together these two changes increased available
compost volume by an amazing 56%! For cottagers, the larger
drum means that it should be unnecessary to extract compost
during the season, almost regardless of how heavily
the unit is use. For residential users, the larger volume means
faster composting and less frequent removal of compost.
Although "Sun-Mar" has made little change to maximum residential
ratings, the larger drum now offers more spare capacity, which
is especially important in residential applications. Introducing
the Mixing Baffle
All 1994 "SUN-MAR" units are fitted with a new, specially
designed mixing baffle to optimize mixing. Now, when
the drum rotates, not only is the tumbling action improved,
but the baffle moves material from the front of the drum
to the rear, and vice versa. The mixing action in the Bio-drum
was very good before. It's now terrific!
Here's to a Longer Fan Life
Experience has shown that the fan is pretty well the only
component in a "SUN-MAR" which is subject to failure. Two
years ago we upgraded to a non-metallic bladed turbo-blower type
fan. 1994 sees a further improvement by having a fan specially
made to "SUN-MAR's" own specifications, which
include dual ball bearings and a corrosion resistant
stainless steel shaft. This 1994 upgrade will extend the service
life, and eliminate stoppages caused by rust, and bearing "wobble".
Do Not Touch!
The push release mechanism we have used to prevent the Bio-drum
from rotating backwards has been very reliable. The only drawback
was that to release it, the user had to put a hand inside the
unit. For reasons we at "SUN-MAR" don't understand, not
everyone was thrilled by this arrangement! So, 1994 brings a change
on all units. The old drum lock is replaced by an elegant pull
release on the front of the drum. Outside the unit!
Zero Block Drains Larger drains on all Central and Non-electric
1994 Models have removed any possibility of peat moss debris falling
through the screen at the rear of the Bio-drum, and causing the
drain to block.
Electric Vent Stack Increase
To reduce friction, and improve air movement, 1994 electric
units are fitted with a 2" vent stack. This change will
be particularly helpful where several 90 degree bends are necessary.
Although the 1995 changes are not nearly as far reaching as those
made in 1994, they represent some important improvements.
Bigger Finishing Drawer
A wider finishing drawer has been designed into all 1995 large
drum units, (that's everything except the "COMPACT" and
"ECOLET") so that 25 % more compost can be extracted
at a time. This improvement has a direct bearing on composting
capacity, because either intervals between extractions can
be lengthened, or, if the same interval is maintained, more
compost is extracted, and available capacity is increased.
A new footrest has been designed for all "EXCEL" family
units, which, by being both narrower and shallower
has a number of advantages over the previous footrest. The narrower
design makes it easy for men to stand with their legs astride
the footrest, while the shallower depth reduces the floor space
New Bowl Liners
Previously, bowl liners had been designed on the "one
must fit all" principle. This resulted in a bowl liner design
that was the lowest common denominator rather than the optimum
design for each unit. In 1995 we have come close to optimizing
the design by producing two different versions, one for the
"COMPACT" and "ECOLET", and the other for the "EXCEL"
family of units. As a result all self contained 1995 toilets
will have greatly improved bowl liners.
In 1995, the composting drums on both non-electric units (EXCEL
N.E." and "CENTREX N.E."), have been fitted with a
high quality foam insulation to help maintain the heat
developed in the compost, and so increase composting speeds.
Insulation has also been fitted to all "CENTREX"
family units because they are normally installed outside. .