Heatrae Sadia FBM 25 ECO 3KW, Installation, Operation And Maintenance Manual, Page: 17 / 40

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WARNING
This appliance must be earthed.
WARNING
The water heater must be connected to
a 230/240V a.c. electrical supply using a
double pole isolating switch fused at 13A,
with a minimum 3mm contact separation
in both poles. The supply cable must be 3
core and each core must have a minimum
cross sectional area of 1.5mm
2
.
6.3.2 Hot Water Outlet
`
An open ended 22mm pipe is provided at the
bottom of the water heater for connection of the
hot water outlet. Using a compression fitting to
connect the outlet pipe to the hot water feed to
the service points. Ensure that a full bore isolating
valve is installed in this outlet pipe work as close to
the water heater as practical.
6.3.3 Breather Pipe
The water heater is provided with a breather pipe
assembly which consists of a short section of 15mm
pipe with a Tundish fitted at one end and a push fit 90
degree reducer at the other end.
`
Push this assembly onto the 22mm pipe at the top
of the water heater. This assembly is designed
to swivel either to the left or the right of the unit.
Decide which side is to be used for the location
of the breather pipe. This pipe must be laid in a
continuous fall and terminate to a safe and visible
location. If a breather pipe already exists move the
assembly to the correct side of the water heater.
`
Once installed connect the breather pipe to the
22mm compression fitting on the Tundish, ensure
connection is tight, secure all pipe work in the
appropriate manner.
6.4 Electrical Installation
WARNING
It is suitable for A.C. supply only.
WARNING
Electrical installation must be carried
out by a competent electrician and be in
accordance with the latest I.E.E wiring
regulations, ensure the electrical supply is
switched off before making any connections
to the unit.
`
Using an appropriate tool, remove the bottom
access panel, retain the screws and panel, place
in a safe location.
`
The supply cable must be routed through the cable
entry point at the bottom of the heater and must be
fed through the cable grip provided with the outer
sheath of the cable firmly secured by tightening the
screws on the cable grip in accordance with the
latest version of BS 7671
`
The cores of the supply cable must be connected
to the terminal block provided, in the following
manner ensuring that each connection is tight:
Earth (coloured green/yellow or green) to Earth
Terminal E
Neutral (coloured blue or black) to termination marked
N.
Live (coloured brown or red) to termination marked L.

If twin and earth cable is used the bare Earth
conductor must be sleeved.
6.4.1 Building Management System Installation
`
To connect the unit to a Building Management
System refer to the electrical wiring diagram in
section 3.3, figure 3, page 8 and Figure 14 below.

The BMS specification to operate the unit remotely
is as follows:
Provide a +5V (10mA) supply supplied from the BMS
interface to the positive (+) connection with respect to (wrt)
the negative (-) connection.
Alternatively provide a +12V (24mA) supply via the BMS
interface to (+) connection (wrt) (-) connection.
Figure 14: BMS Wiring
CAUTION
Do not use a solder fitting
1
2
3
4
5
6
CAUTION
Inclusion of a non return valve and or a
pressure reducing valve may be required
when using a mixer tap to prevent back flow.