Graf one2clean User manual

Document No. Graf-0003 Rev. 1
ONECLEAN TANKS
INSTALLATION
MANUAL

. GENERAL NOTES
Graf UK Ltd

GENERAL NOTES
Safety
The relevant accident prevention regulations must be
observed during all work. Particularly when walking on
the tanks, a 2nd person is required to secure the tank.
The relevant regulations and standards must
additionally be taken into consideration during
installation, assembly, servicing, repair, etc.
The system or individual parts of the system must be
installed by qualified specialists.
During all work on the system or parts of the system,
the entire system must always be rendered inoperable
and secured to prevent unauthorised reactivation.
Except in the event of work carried out in the tank, the
cover of the tank must always be kept sealed, as this
otherwise constitutes a maximum risk of accident. Only
original GRAF covers or covers approved in writing by
GRAF must be used.
GRAF oers an extensive range of accessories, all of
which are designed to match each other and which can
be extended to form complete systems.
The use of other accessories may lead to impediments
to the system’s functional capability, therefore
invalidating liability for resulting damage.
1

. INSTALLATION CONDITIONS
Graf UK Ltd 
Coverage heights with telescopic dome shaft in green
areas.
Maximum coverage heights with extensions and
telescopic dome shaft.
Covering heights with cast telescopic dome shaft (with
class B cast cover) in areas with car trac (load up to
3.5 t).
Coverage heights with vehicle loading cover (suitable
cover to be provided by others) in areas used by trucks
with a max. weight of 12 t.
Coverage heights on installation in groundwater the
hatched area specifies the permissible immersion
depth for the tanks.
The immersion depth is 350 mm.
2INSTALLATION CONDITIONS
1200
Mini telescopic
dome shaft
Maxi telescopic with cast iron lid
>800<1200
max 12 to
>800<1200
>800<1200
max.
350mm

. TANK INVERT LEVELS
Graf UK Ltd

TANK INVERT LEVELS
3
Population Equivalent 5 PE 7 PE 9 PE
Tank 3750 litres 4800 litres 6500 litres
Max. daily inflow 750 l/d 1050 l/d 1350 l/d
Weight with mini tank dome 146kg 181kg 220kg
Weight with maxi tank dome 150kg 185kg 220kg
L 2280mm 2280mm 2390mm
W 1755mm 1985 mm 2190mm
H-Inv - 1390mm 1575mm 1840mm
H-Inv + * 630 to 1460mm
H-Tot 2020 to 2790mm 2250 to 3020mm 2530 to 3300mm
650
LW
290
Inlet Level
(varies with tank size)
H-Inv +
H-Inv -
H-Tot
650
LW
610
Inlet Level
(varies with tank size)
H-Inv +
H-Inv -
H-Tot
With mini tank dome
With maxi tank dome
* Various inlet options available to suit installation. Please specify invert depth required when ordering.

. TANK INSTALLATION
Graf UK Ltd 
TANK INSTALLATION
4
1. Subsoil
2. Telescopic dome shaft
3. Compact foundation
4. Surrounding (round-grained gravel, maximum grain size 10 to 20mm)
5. Covering layer
6. Carat underground tank
7. Concrete layer for surfaces used by passenger cars
1 4 7
63
2 5

. TANK INSTALLATION
Graf UK Ltd

TANK INSTALLATION
Trench
To ensure that sucient space is available for working, the base area of the trench must exceed the dimensions of
the tank by 500mm on each side; the distance from solid constructions must be at least 1000mm.
The trench embankment must be designed so that slippage or collapse of the embankment wall is not to be
anticipated. The construction site must be horizontal and plane and must guarantee sucient loadbearing capacity.
The depth of the trench must be dimensioned so that the max. earth coverage (see point 2 installation conditions)
above the tank is not exceeded. To use the system throughout the entire year, it is necessary to install the tank and
those parts of the system which conduct water in the frost-free area. The frost-free depth is usually approx. 600mm
to 800mm; precise information in this regard can be obtained from the responsible authority.
A layer of compacted, round-grain gravel (grain size 10 to 20mm, thickness approx. 150 - 200mm) is applied as the
foundation.
Slope, embankment, etc.
On installation of the tank in the immediate vicinity
(< 5m) of a slope, earthen mound or slope, a statically
calculated supporting wall must be erected to absorb
the soil pressure. The wall must exceed the dimensions
of the tank by at least 500mm in all directions, and
must be located at least 1000mm away from the tank.
Groundwater and cohesive (water-
impermeable) soils (e.g. clay soil)
If it is anticipated that the tanks will be immersed
deeper into the groundwater than is shown in the
adjacent figure, sucient dissipation must be ensured.
(See table for max. immersion depth).
Dissipation of the drainage water (e.g. via an annular
drainage system) is recommended in the case of
cohesive, water-impermeable soils.
Installation adjacent to surfaces used by
vehicles
If the underground tanks are installed adjacent to
surfaces which are used by vehicles heavier than
passenger cars, the minimum distance away from
these surfaces is at least the depth of the trench.
4
Population Equivalent 5 PE 7 PE 9PE
Tank size 3750 4800 L 6500
Immersion depth 350mm 350mm 350mm
>800<1200
max.
350mm

. TANK INSTALLATION
Graf UK Ltd 
Insertion and lling
The tanks must be inserted, impact-free, into the
prepared trench using suitable equipment. The tank is
filled with 1/3 water before starting to backfill.
Afterwards the surrounding (roundgrain gravel,
max. grain size 10 to 20mm) is then filled in layers of
max. 30 cm steps and is compacted. The individual
layers should be manually tampered to ensure no
voids. Damage to the tank must be avoided during
compaction. Mechanical compaction machines must
not be used under any circumstances. The surrounding
must be at least 500mm wide.
Ventilation and bleeding
Poor venting and the lack of a Soil Vent Pipe is the
number one cause of smells from treatment plants. All
tanks must be ventilated and bled back through the
soil vent pipe (chimney eect). Air Admittance Valves
(Durgo Valves) must not be used instead of the SVP.
These valves are fine for houses connected to mains
drainage but NOT for ones with a treatment plant.
4TANK INSTALLATION
Bleeding with a free outflow
Bleeding with percolation or an
obstructed outflow
1. 1/3
2. 3/3
500

. TANK INSTALLATION
Graf UK Ltd

TANK INSTALLATION
Assembling the telescopic dome sha
The telescopic dome shaft enables infinite adaptation
of the tank to given site surfaces with earth coverage
of between 750mm and 950mm (Mini telescopic dome
shaft) or 750mm and 1050mm (Maxi telescopic dome
shaft).
For assembly purposes, the enclosed profile seal
(material EPDM) is inserted into the tank dome’s
sealing groove and is coated generously with soft
soap (do not use mineral oil-based lubricants, as
these attack the seal). The telescope is then greased,
inserted and aligned with the surface of the site.
Telescopic dome sha on which persons may
walk
Important: To prevent loads from being transferred
onto the tank, round-grain gravel 1(max. grain size 10
to 20mm) is filled in in layers around the telescope 2
and is evenly compacted.
Damage to the tank dome 3and telescope must be
avoided during this step. The cover is then positioned
and is sealed to prevent entry by children. Tighten the
threaded connection on the cover so tightly that it
cannot be opened by a child!
Telescopic dome sha over which passenger
cars may drive
If the tank is installed under areas used by passenger
cars, the collar area of the telescope 1(colour
anthracite) must be supported with concrete 4(load
class B25 = 250 kg/m²). The layer of concrete to be
installed must be at least 300mm wide and approx.
200 mm high all around. The minimum coverage above
the shoulder of the tank is at least 800mm (max.
1050mm with telescope, coverage up to max. 1200mm
possible with intermediate section).
Attention: It is essential to use the cast telescopic
dome shaft (with class B cast cover).
4
4
2
3
1
1
3
2

. TANK INSTALLATION
Graf UK Ltd 
Assembling the extension
For larger coverage heights an extension is needed.
To insert the extension into the tank dome, soft soap
is needed. Into the highest groove of the extension
the profile seal is inserted and greased generously.
Afterwards push the telescopic dome shaft into the
extension and adapt it to the planned area surface. The
extension must not be cut down.
1 Extension = max. earth-cover 1200mm
(in each case in connection with the Maxi telescopic
dome shaft)
1 Telescopic dome shaft (can be inclined by 5°)
2 Extension
3 Tank dome (can be rotated by 360°)
4TANK INSTALLATION
Cut line
2
3
1
Seal

. INTERNAL CABINET
Graf UK Ltd

Ground First
WWT inlet pipe
The One2clean control panel supplies compressed air
through a 19mm and 13mm Hose to the underground tank.
Hoses should be housed inside 4" drainage pipe or similar.
Internal Sampling
Chamber
To drainage field or water course
Wastewater level
Tubular diffuser located in the base of tank
Below ground
Wastewater Tank.
625
Soil Stack
All treatable waste water to enter
treatment plant via soil stack
Clear water discharge pipe tubular
diffuser located in the base of tank
DN100
< 18m
WC
13mm PVC Hose (black/red)
Fixed with Jubilee Clip
19mm PVC Hose (blue)
Fixed with Jubilee Clip
13mm PVC Hose (black/red)
Fixed with Jubilee Clip
19mm PVC Hose (blue)
Fixed with Jubilee Clip
One2clean Internal Control Panel
The controller requires its own,
permanent adequately fused (13
amp) 230V power supply. Fitted
with Isolator switch for
maintenance and repair
Low level air vent
DO NOT SCALE - IF IN DOUBT ASK
DRAWING No.
P0
REV.
DESCRIPTION
INTERNAL CABINET
PROJECT
ONE2CLEAN
DRAWN : CHECKED :
DS MC
DATE : SCALE :
07.10.20 NTS@A3
ISSUE
REV.
P0
DESCRIPTION BY FOR GUIDANCE DS 07.10.20
DATE
THIS DOCUMENT IS SUPPLIED IN STRICT CONFIDENCE AND MUST NOT
BE LENT, REPRODUCED OR DISCLOSED TO ANY THIRD PARTY WITHOUT
THE WRITTEN CONSENT OF SCP WATER MANAGEMENT LIMITED
NOTES:-
GRAF UK Limited
Graf UK Limited | Regen House | Beaumont Road | Banbury | OX16 1RH
T: 01608 661500 F: 01295 211333
E: [email protected] www.grafuk.co.uk
ONE2CLEAN_INTERNAL CABINET