3.
Boiler Characteristics.
3.
1 The C24/C28 is a
fon
tlued, wall
-m
ou
n
ted
condensing
type
com
bina
ti
on
boile
r
that
suppJics
both
cc
nm
d hcat
Ulg
and
ma
in
i.
fed
d
om
est
ic hnt water. Bei
ng
room
,,;
ea
l
ed
the-boiler may
be
in
sLa
lled
in
illl)
'
room
or
ini
ernalcompartrnent without the need
for
p
urp
ose
ma
de
ve
ntila
ti
on.
A
functiona
J
di
agram
of
rh
e
boiler's
principal
componeDts
isgi
ven
asf,gure I .
3.2 R
ange
ra
1
ed
from 24k\V
to
28kW
C24
/C28.
hea
t
ou1put
can
be
foc
used
to
matc
h the designed heating systems requirements
by
a simple udjm,iment.
3.3 An
cl
e<:rroni
c control
t1o
it, consisting
of
a P
CB
,vhi
ch
includes
ignition
mo
du
le provides dire
ct
bu
rner
ig
.ni
tio
n
and
Oame
supervisi
on
along with c
on
l"
inuous modulation
of
th
e
hu
me:r
~
gas
supp
ly.
3.4
An
in
terface: unit, which includes boiler adjustment
polc:
ntiometers
Md
fo
:uh
display provides easy service
ab
ility
to
l
he
boil
er
.
3,5 Heattransfer to the
boi
ler
's
primary hydrau
li
c clrcuil
is
obtained
via a primar
y,
g.as
lo water heat exchanger contained wit
hi
n a
herme
tica
llysealed
combustion
ch
ambe
r.
A 230 volt,singlespeed
fan
ex
pe
ls
the
prodUQS
or
combustion
from
ll.1c
com
bu
stion
ch
amber
to
ouLo;;
ide
a.fr
,·ia an
llS$ocia.ted
Oue system. The
fa
n is
ac
tivated
atlhebeginning
of
eachignitioncycle and i
ts
operati
on
m0nitored
by
means
of
negativeand positivesensing
poin
ts co
W1
cctOO
to an
a
ir
pr
ess
u
re
switch.
8
3.6A secondary beat e."cbang
er
allows the instant
aneo1
1s transferral
of
beat from the
pr.iruary
bydrau
lfo
circuit to
v..-atcr
destined
fo
r
domestic h
ot
wate
r use.1"he
seocm
clary heat exchanger is siz.ed so
as
to
minim
ise lhe-
nnoJ
sl1ock
andisprotected against the build up
of
lime scale by Limiting the
D.H.W
.oudet water temperature to
a
max.jroum
~f
64°C.
3.7
An integral pump located in the boilers main hydra
uUc
circuit
circul
ates
w.=itcr
through
the
primary h
ea
t
exchanger
ro
eitherthe
ccntra) healing c.ircuit
flT
O.H.
W.
heat exchanger, depending on
lhe
demand. Jn lhe
event
ofred
uced
or
interrupted.
watercirculation
in
the
cemml
beating
circu
it
tl1c
prima
ry
hoo
tex
ch
anger is
prote.ctcd
by
an automatic
by
-pass v
al
ve
calibrated to e
ns
ure a minimum
Oow
of
S00
-6
00
liL
re,./hr. A system by-
pai
>s shoultl
be:
fitted 1
,s
far
awa
y
ftotu
the
boil
er
as
possible
.
3.8 Room tempera
tu
recan
Ix:
oont-mllcd
by
theuse
nf
an
externa
l.
room
tbenno
sta.t
or.
a temperntureregulator(Lirnerthe
rm
ostatwi
th
output
contact).
3.9
The
C.H.
sy
stem
tem
pi:ntlurc:
1.:a
n be adjusted due 10
uuldo
or
tempe
rarure
byconnectingan
OUtdoorTemperature
sensordil-«.tly
to the
ma
in PCB.
3.
10
A1on
gwith
an
integral t
im
eeonuol
to
allow
th
e
se.tt
in
g
of
central
beati
ng
period
s.
tile
boiler's control pan
cJ
inc01poratos
a.
LED
diagoostic
di
splay
fo
ri
nd
ica
ti
ng
st.1tc
of
opcr:ll
i
oo.
faul
t
and
<le
feet
c:xl<lcs
.
