Glow-worm ASCOT 1.4S - Page 7

The minimum
water pressure
required
to
fully open
the
gas valve
is 2.29m
(?.5f0.
However,
where
the water
pressure
is limited,
for
example
on
a
cistern
supply,
then
for
practical
purposes
a
head
of 3.29m
(l0ft10in)
is
required
witlr
normal piping
to
give
a
water flow rate
o[
T.llitres/m
(l.6gallmin)
and a temperature rise of
4aoC
(80oD.
The head
of
water is
measured
vertically
between
the level
of
the water in
the cistern and the level
of the
highest hot water
draw
off
tap. For
direct
mains
connections,
(subject
to
local
water
company
regulations),
tie size may
be 15mm copper tube to
BS287l
where
sufficient
pressure
is
available.
If
the heater
is fitted
to
a mains
supply
which is
subject to
variable
high
pressures,
it is
recommended
that
a water
governor
is
fitted to the
heater inlet
pipe.
A
suitable
governor
is the
Dereve
010521o4, available from
Dereve
flow
Conuols)
Ltd.,
Park Lane, Handsworth,
Birmingham,. B21
8LE telephone 027
553
7021. If
a
warer
pressure
limiter
is required this
may
be
connecred into rhe
water pipework
adjacent
to the heater
or
may
be
fitted
on
the heater,
after
removal
of the
venturi
cap, see diagram
10.
If the
inlet
tail is
ro
be soldered
into
rhe
supply
system
it is recommended
that
the
water
service
cock
be
removed whilst
maling the
joinr.
This is
to eliminate
the risk
of damaging rhe
seal in the
service
cock.
Flush
out
all foreign
marter
from the
supply
pipe
BEFORE
connecting
to
r.he
heater.
Connect the
hoc
water
system to the
water
outlet
tail, see diagram
11.
Check
rhar there
are
no
water
leals
after connection.
Ensure
that
all
the air is
expelled fron; ihe
rvater
system
by tunring on ALL hot warer
dra,r, off raps
and
then turning
them
off
in
sequence,
snrting
with
the
draw
off
tap
at the
lowest level.
Refit the
outer case.
3.5
Gas
Connections
The
gas
supply connecrion
is
made
by rhe i5mm
o.d
copper
uil
pipe.
This
is
supplied
loose wirh
the
gas
service cock.
They
should
be assembled as
shown
in
diagram
9.
When
making
the
connection it
is
important
rhar:
a) The
gas
inlet
pipe
musr pass
above
rhe
thermocouple
and union
nut.
b)
The
service cock
be
removed
during rhe
soldering
process
if
rhe inlet
rail is
soldered
into the
supply
sysrem. This
is
ro
eliminare
the risk
of
damaging
rhe
service
cock
seal.
c) The
pipes
are
blown rhrough
before connccrion
to
prevent
forcign
matter
entcring
the
heatcr.
The size of
a
straight unrestricted
gas
supply
from
the
meter to the
heater
should be as
follows:
Disunce
from meter Gas
supply outlet
to heater
outside diameter
l5mm
22mm
Consult the
local
gas
company
These sizes
are for
the
heater
only and
do
not
take
account
of any
other
gas
appliances
which may be
connected
to the
same
gas
service
pipework.
0-3m
(0-10ft)
3-20rn
(10-65f0
20m
(65ft)and
above
OFF
POSITION
(Turn
90"
for
on
position)
N
INLET
WATER
CONNECTION
Diagram 7
WATER
SERVICE
COCK
GAS
INLET
CONNECTION
N
l-.
Diagram
B
GAS
PRESSURE
TEST POINT
GAS
INLET
TAIL
PIPE
GAS SERVICE
COCK
(Shown
in
'OFF'
position)
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