
6 720 610 576 GB (03.02)
12
Installation
3 Installation
3.1 Important remarks
BAppliance should only be ins alled in sealed cen ral
hea ing sys ems.
BTo avoid gas forma ion in he sys em, galvanised
radia ors or pipes mus no be used.
BIf a room hermos a is used: do no fi a hermos a ic
radia or valve on he radia or in he primary room.
BAdd a sui able an i-freeze fluid compa ible wi h alu-
minium o he wa er in he cen ral hea ing sys em.
Sui able produc s are available from Be z-Dearborn
Tel.: 0151 4209563 and Fernox Tel.: 01799
550811.
BIn our experience, he addi ion of sealing agen s o
he wa er in he cen ral hea ing sys em can cause
problems (deposi s in he hea exchanger). For ha
reason we advise agains heir use.
3.2 Domestic hot water
Any regula ions specified by he local wa er company
mus be observed.
The final 600 mm of he mains cold wa er connec ion o
he applaince should be made in copper ube only.
The appliance is sui able for a mains supply having a
maximum pressure of 10 bar. A pressure reducing valve
mus be fi ed, if necessary.
The ho wa er ou le empera ure is se o be capable of
achieving a maximum of 60˚C. The maximum empera-
ure and he frequency of he recharge of he hea s ore
may be rese .
A wa er flow ra e of 9.9 l/min (ZWB 7-25) and
10.4 l/min (ZWB 7-30) will give a empera ure rise of
40˚C. If a higher rise is required hen he flow mus be
reduced a he ap and he discharge empera ure will
rise up o he maximum se figure.
The empera ure rise, up o he maximum se by he user,
is au oma ically main ained by he modula ion of he
hea inpu . In win er, when he mains empera ure is
very low, he wa er flow, adjus ed a he ap or shower,
should be reduced o main ain he required delivery
empera ure.
I is sugges ed ha long pipe runs o aps or showers
be insula ed o preven he rapid cooling of he wa er.
All ypes of single lever mixer aps and hermos a ic
mixer uni s sui able for a mains pressure of up o 10 bar
can be used.
The head of a loose-head shower mus no be allowed
o fall wi hin 25 mm of he op he ba h o preven he
risk of wa er being drawn back in o he mains. Al erna-
ively he shower mus be fi ed wi h an an i-syphonage
device a he poin of he flexible hose connec ions.
Over-rim bide s may be connec ed o he appliance
provided ha i is in accordance wi h he requiremen s
of he local wa er company. The ou le (s) should be
shrouded and unable o have any emporary hand held
spray a ached. No an i-syphonage arrangemen s are
necessary.
In excep ionally hard wa er areas a device o preven
scale forma ion may be fi ed or, al erna ively, he maxi-
mum empera ure rese o abou 45˚C which may
reduce he risk of scale forma ion. The ins alla ion of a
scale inhibi or assembly should be in accordance wi h
he requiremen s of he local wa er company. Ar ificially
sof ened wa er mus no be used o fill he cen ral hea -
ing sys em. An isola ing valve should be fi ed o allow
for servicing.
Devices, such as water meters or back-flow pre-
vention valves, capable of preventing the flow of
expansion water must not be fitted unless sepa-
rate arrangements have been made.
A Zilme Z160 expansion vessel is he preferred ype. A
hread sealan compa ible wi h po able wa er mus be
used. The vessel should be connec ed in o he cold
wa er mains inle pipe as close as possible o he appli-
ance.
3.3 Sealed systems
The appliance mus no be opera ed wi hou he sys em
being full of wa er, properly ven ed and pressurised.
The expansion vessel has a volume of 10 li res and is
charged o a pressure of 0.75 bar.
The wa er capaci y of he sys em is shown in able 12,
page 27. If a grea er capaci y is required hen an addi-
ional expansion vessel mus be fi ed in o he sys em
re urn as close o he appliance as possible. The sys em
pressure can be se up o a maximum of 1.5 bar wi h 1
bar being he normal se ing.
If he sys em pressure is grea er han 2.65 bar when he
appliance is opera ing a maximum empera ure hen an
addi ional expansion vessel mus be fi ed in o he sys-
em re urn as close o he appliance as possible.
The filling poin mus be a low level and arranged as
shown in figs. 5 and 6.
The pressure relief valve is se o opera e a 3 bar.
There mus be no connec ion o he mains wi hou he
approval of he local wa er company. All connec ions in
he sys em mus be capable of wi hs anding a pressure
of up o 3 bar and he radia or valves conform o he
requiremen s of BS 2767:10.
BAlways urn off he gas cock before car-
rying ou any work on componen s
which carry gas.
iFixing of he appliance, gas and flue con-
nec ions, commissioning of he sys em
and elec rical connec ions may only be
carried ou by compe en persons au hor-
ised by CORGI.