3. Add a T-fitting and a valve (not provided) to the domestic hot water
tank drain outlet.
6.3 Water connections
6.3.1 Connecting the domestic hot water tank to the drinking wa
ter mains
1. Flush the drinking water inlet pipes in order to prevent metal or other
particles from entering the appliance's tank.
2. Hydraulically isolate the domestic water circuit with a stop valve to
facilitate maintenance operations on the domestic hot water tank.
3. Install a pressure reducer if the mains pressure exceeds 80% of the
calibration of the safety valve or unit (e.g. 5.5 bar (0.55 MPa) for a
safety unit calibrated to 7 bar (0.7 MPa)).
Caution
The pressure reducer must be installed upstream of the appliance
and downstream of the water meter in such a way as to ensure
the same pressure in all of the system's pipes.
4. Install a non-return valve between the safety unit and the pressure
reducer to prevent the backflow of domestic hot water into the do
mestic cold water circuit.
5. Incorporate a sealed safety valve calibrated to 7 bar (0.7 MPa) (not
provided) on the domestic cold water inlet, close to the tank, in a po
sition which is easy to reach.
Caution
There must be no cut-off devices between the safety valve or unit
and the domestic hot water tank.
Note
Mount the safety valve above the domestic hot water tank to avoid
having to drain the domestic hot water tank when working on it.
Note
Install a water drain in the boiler room and a funnel-siphon for the
safety unit.
Note
6. Install the drain valve at the bottom of the domestic hot water tank.
7. Make the connection to the domestic cold water.
See
Hydraulic installation diagram shown in the boiler's installation and
maintenance manual.
Safety unit discharge pipe
To avoid restricting the flow of water in the event of overpressure:
The safety unit discharge pipe must be kept in the open, in a frost-free
environment, and have a continuous, downward gradient.
Fig.15 Adding a T-fitting and a valve.
MW-3000225-1
3
6 Installation
7626247 - v03 - 29042016
EL 110 SL
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