Hot water storage
The Safety Unit :
(EN 1487 standard).
Main safety unit,
its installation is mandatory
This appliance performs
4 functions :
As the water temperature increases, the
pressure also increases inside the water tank
(dilation of the water).
For safety reasons, this pressure must be
restricted to a value lower than the tank's
This function is carried out by the safety valve
which is set at 7 bars.
Isolating the hot water tank from the cold
water supply :
This function is carried out by the stop valve
(also part of the Safety Unit).
Preventing a backflow of cold water into the
cold water supply system :
A check valve prevents any backflow of hot
water (which is under pressure in the tank) into
the cold water supply system, as soon as the
pressure in the tank becomes higher than that
of the cold water supply.
Draining the tank :
The tank is drained using the safety valve
which can be activated manually, and once
opened, the water held under pressure in the
tank is drained out.
(Caution : make sure that the electrical
connection of the tank has been previously
disconnected. In addition, take precautions
against burns during hot water drainage).
The drainage outlet on the Safety Unit, which
comprises an air gap preventing any backflow
of the drained water, should be connected to
the drainage system.
Pressure reducing valves :
This reduces the pressure of the water that
crosses it and provides an outlet pre-set and
The REDUFIX model protects, in particular, the
electric tank and it is factory pre-set. During the
night, when the pressure of the water
distribution system increases (at night the
pressure of the water distribution system
increases with the reduction in the number of
water consumers), the pressure reducer
protects the tank against excess pressure, as
well as prevents the opening of the Safety Unit
The trap funnel kit :
As indicated by its name this part works as a
trap : the screwing part is placed directly under
the Safety Unit at the threaded male discharge
in 1" (26x34).
The smooth part, to be glued, is connected to
This trap complies with the requirements of the
NF standard, with a sufficiently sized air gap
and water gap, protecting the bad odours from
Dielectric union :
Two different metals, copper and steel (for
example), coming in contact in an equipment
results in corrosion risk.
Copper and its alloys (such as brass) are
cathodic, which associated with other metals
foster "battery" phenomena and, as a result,
cause faster corrosion and circulation of stray
The dielectric unions provide connection of
cold water tubulature (made of steel) of the
Safety Unit tank (made of brass) without
creating a "battery" phenomenon. This union
fitting is removable, which facilitates
We also recommend that the hot water outlet
of the tank is protected with a dielectric
The Watts Industries dielectric unions meet the
requirements of the D.T.U. in the framework of
the implementation of protection against the
corrosion of some pipes including steel and
copper components; in particular, this is the
D.T.U 60.1 regarding sanitary plumbing in
The thermostatic mixing
valves MMV-C :
This unit automatically mixes the hot water in
the tank with the cold water in the water supply
It provides several functions :
Safety : it automatically provides and stabilizes
mixed water at the selected temperature.
(from 30° to 65°C).
Saves hot water : the hot water pipe lines are
only filled with mixed water.
A large supply of hot water is still available.
The pipes and taps are highly protected
against lime scale.
Compliance with regulations:
It satisfies the obligations imposed by the
Ministry decree of 30th November 2005,
applicable as from 15th December 2006,
prohibiting any water distribution at a
temperature over 50°C at the point of use in
bathrooms. Adjusting the appliance (to be
done only once at the time of installation) is
facilitated by the handle button: Lowering of
the temperature by turning clockwise, increase
of the temperature by turning anti-clockwise.
The appliance is fitted with built-in non-return
Trap funnel kit
Electric hot water
Application diagram (example)