STIEBEL ELTRON ESH 120 Trend GB Operation And Installation Manual page 9

iNSTALLATiON
Appliance installation
9.2.3 Tundish
The recommended position of the tundish is to the left of the DHW
cylinder when viewed from the front.
f Connect the inlet end of the tundish to the outlet end of the
flexible Y hose.
Note
The tundish must be positioned where it can be seen and
away from any electrical devices.
f The tundish can be secured with the screws supplied.
9.2.4 Secondary return
A secondary return can be connected between the expansion
vessel and the expansion connection, via a tee (not part of the
standard delivery).
Note
- If the secondary return circuit exceeds 10 % of the
cylinder capacity, an additional expansion vessel is
required.
- To ensure the correct direction of flow, the second-
ary return must be pumped by a bronze pump and
must be fitted with non-return valves.
9.2.5 Discharge pipe
The discharge pipe must be intended for the DHW cylinder and
may not be used for other purposes.
f Connect the outlet of the tundish to the discharge pipe.
f Install the tundish in a vertical position, at a maximum dis-
tance of 500 mm from the drain connector of the temperature
and pressure limiter.
f Ensure that the discharge pipe drains through the tundish.
- The pipework of the tundish must have a diameter of 22 mm
and a vertical minimum length of 300 mm below the tundish.
- The maximum permissible length of the ø22 mm pipework is
9 m.
- Every bend or curve corresponds to 0.8 m of pipework.
Note
All pipework must have a constant fall and must dis-
charge in a safe, visible location. If in doubt, consult
building regulation G3.
Outlet pipe - alternative discharge
- The discharge pipes must be made of metal. Any modifica-
tions to discharge pipes must be heat-resistant in accordance
with the G3 building regulations.
- The pipe must have a constant fall.
- The pipe end must be in a safe and clearly visible location.
- Discharge outlets at low height, e.g. up to 100 mm above
exterior surfaces such as car parks, paved surfaces, lawns,
etc. are permissible. The condition for this is that in locations
where children play or may otherwise come into contact with
the discharge outlet, a wire mesh or similar safeguard is fit-
ted over the outlet to prevent contact and ensure visibility.
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- Discharge outlets at great heights must lead into a metal
funnel and a metal downpipe (tundish visible or not) or must
discharge on to a roof that is resistant to very hot water. The
outlet must be at least 3 m away from any plastic guttering
that might collect the discharged water (tundish visible). The
end of the discharge pipe must be clearly visible.
- If several discharge pipes are merged into a single pipe, e.g.
in apartment blocks, the number of supplied systems must
not exceed 6, to ensure each discharge pipe can easily be
traced back.
- The cumulative pipe must be at least one pipe size larger
than the biggest discharge pipe being connected.
Note
For further information, contact your local authority plan-
ning department.
1
2
4
1 Safety device (e.g. temperature relief valve)
2 Metal discharge pipe (D1) from temperature relief valve to
tundish
3 Tundish
4 Discharge pipe (D2) from tundish with constant fall
5 Discharge below fixed grating
6 Fixed grating
7 Drain
Valve outlet minimum minimum
size size of dis- size of dis-
charge pipe charge pipe
D1 D2 from
tundish
[mm] [mm]
G 1/2 15 22
28
35
G 3/4 22 28
35
42
G 1 28 35
42
54
3
5
6
7
maximum resistance
permissible generated
resistance, by each
expressed bend or
as length elbow
of straight
pipe (with-
out bend or
elbow)
[m] [m]
≤ 9 0.8
≤ 18 1.0
≤ 27 1.4
≤ 9 1.0
≤ 18 1.4
≤ 27 1.7
≤ 9 1.4
≤ 18 1.7
≤ 27 2.3
ESH Trend GB | 9