water overboard, provided it is lawful to do so.
The pump has a bore of dia. 38 mm.
When the tank is pumped empty by a high capacity pump, there
is a risk of the tank collapsing due to the under-pressure. This
problem occurs especially with 'pump-out systems'.In order to
prevent the tank collapsing, one of the following measures can
- Open the tank inspection cover.
- Open a valve specially fitted in the tank for this purpose.
- Install an automatic relief valve.
- Install a 38 mm dia. ventilation pipe.
After pumping the tank empty:
Rinse the tank with clean water, so that all the discharge hoses
are filled with clean water.
During your absence
Flush the toilet several times to ensure the hose linking the toilet
and the tank is filled with clean water to avoid smells when not
Clean and sterilize the tank and pipes at least once a year, preferably
at the end of the season.
Black water tank
Clean the inside of the tank with water and a good toilet
cleaner, use household vinegar when there are scale deposits.
Use a brush or sponge on a rigid tank. Rinse the tank with
clean tap water.
Sterilize the tank by filling with a solution of chlorine bleach
in water (1 : 1000). Allow this solution to circulate through the
waste water system. Remove the solution and rinse tank with
clean tap water.
When choosing a place for the tank and for the deck filler cap,
take the following into account:
The suction hose should be as short as possible, must go
directly down to the tank and be as straight as possible.
The space in which the tank is placed should be properly ventilated.
Several toilets may be connected to a single tank. Extra fittings
are also available.
Position the tank as close as possible to the toilet to avoid dirty
water flowing back into the toilet from the tank when the boat
Arrange the tanks, and thus the weight, evenly over the ship.
Install the tank so that it is easily accessible for inspection.
Also ensure that there is sufficient free space over the top of the
tank for the hose connections. These must be easily accessible
during installation. The tank should be 1 cm. free all round from
bulkheads or other tanks, to provide ventilation.
Make sure that the foundation for the tank is strong enough
to locate it securely. The tank will increase in size slightly when
filled. Take this into account when securing the tank. Attach the
tank using the stainless steel rings supplied.
Inspection cover and fittings
The inspection cover and the fittings are pre-assembled in the
upper section of the tank.
Use the tool provided to fit the fittings in the correct direction.
If required create additional
holes on the top of the
tank for extra fittings (43
Choose the position of
the fittings so that when
the ship is beached on its
side, waste water cannot
run back to the toilet, or
flow outside via the tank
Clean saw dust and drill shavings from inside the tank.
Assemble the fittings with the
gasket rings supplied. Tighten the
nuts using the wrench, never with
water-pump pliers. Do not tighten
the nuts excessively.
After 2 days check that the connector
nuts are still tight, tighten
more securely if required. Repeat
this after 4 days.
To prevent blockages caused by
hairs and coarse waste in particular,
all fittings should have burrs
removed internally, local narrowing
should be reduced to a minimum
and any changes in pipe
diameter should be done using conical
adapters or large radii.
The sensor for a dirty water level meter is already fitted in the
top of the tank.
The sensor can be connected only to a Vetus level indicator
for waste water.
Option: Vacuum operated vent valve VRF56
In the top of the tank, drill the hole for the vent valve (dia. 57).
Connect the tank with a good quality reinforced
hose. Avoid sharp bends and kinks or sagging in
Bracket the hose at not too far apart, regular points,
to prevent the hose sagging. Deposits will collect in
these sags, causing a blockage after time.
The reinforced hose should be an odour-proof
waste water hose and resistant to a limited underand
over-pressure of 0.3 bar (0.3 kgf/cm2, 4 psi).
Vetus supplies a hose suitable for waste water.
Specially for black water tanks:
SAHOSE16, odour-proof waste water hose,
16-mm (5/8") internal diameter
SAHOSE19, odour-proof waste water hose,
19-mm (3/4") internal diameter
SAHOSE25, odour-proof waste water hose,
25-mm (1") internal diameter
SAHOSE38, odour-proof waste water hose,
38-mm (1 ½") internal diameter.
Fit every hose connection with a good stainless
steel hose clip.
Attach the discharge connection '5' to waste
water pump '9'.
To assemble the valve correctly, consult the waste
water pump manual.
Install hull outlet with valve '11'.
Install the suction hose '17' (38 mm. dia.) such that neither
the tank, pump or deck cap are subject to any mechanical
Fit the air-relief nipple '14' as high up as possible above the
level of the top of the tank. Choose a place for the nipple where
rain or other outside water cannot enter.
If required, fit an odour filter '15' between the air-relief pipe and
Fit the air-relief pipe '18', internal diameter 16 mm (5/8"),
between the air-relief nipple and the tank. When viewed from the
tank, the air-relief pipe should run straight upwards.
Install a bend ventilator '10' in the discharge pipe between
pump and hull outlet when the waste water tank is below the
water line and the hull outlet is also below the water line.
If the suction connector '3' is not being used, close the suction
pipe off with a plug.
Preparation for winter
The tank, pipes, pump, etc., should always be drained.
Never add anti-freeze to the tank or other parts of the waste
water system to protect against frost damage. Anti-freeze is
Propylene-based anti-freeze may be used.
Clean the tank according to the cleaning procedure.
Regularly check the air-relief nipple and clean its sieve if necessary.
Regularly check the hoses and hose connections for possible
leaks and fit new hoses and/or hose clips when necessary.
Also check the tank for damage caused by abrasion. Replace a
damaged tank immediately.
At the end of the cruising season, carry out the cleaning and
sterilizing procedures as described under 'Use'.
A tank and installation which is seriously polluted with algae can
be cleaned by thoroughly rinsing out the tank, pump and pipes
Waste water tank system
|Max. Pressure :
||30 kPa (0.3 bar, 4 psi)
||Polyethylene, colour: black
|For filling hose :
||38/35/25/19/16 mm dia.
|For discharge hose :
||38 mm dia.
|For air relief :
||19 mm dia.
|For discharge :
||38 mm dia.
Fittings for hose with suction tube
For Vetus waste water deck cap: 38 mm dia. (1 ½" dia.)
*) Nominal values are given for capacity and weight. Slight
deviations are possible.