Installation
19
│
Page
Do
not
use
this
water
heater
if
any
part
has
been
submersed
under
water.
Immediately
call
a
licensed
professional
to
inspect
the
water
heater
and
to
replace
any
damaged
parts.
WATER
CONNECTIONS
1.
All
pipes,
pipe
fittings,
valves
and
other
components,
including
soldering
materials,
must
be
suitable
for
potable
water
systems.
2.
A
manual
shut
off
valve
must
be
installed
on
the
cold
water
inlet
to
the
water
heater
between
the
main
water
supply
line
and
the
T
‐
H2
‐
DV/T
‐
H2
‐
OS.
3.
In
addition,
a
manual
shut
off
valve
is
also
recommended
on
the
hot
water
outlet
of
the
unit.
If
the
T
‐
H2
‐
DV/T
‐
H2
‐
OS
is
installed
within,
or
subjected
to,
a
closed
loop
water
system,
a
thermal
expansion
tank
must
be
installed.
4.
Before
installing
the
water
heater,
flush
the
water
line
to
remove
all
debris,
and
after
installation
is
complete,
purge
the
air
from
the
line.
Failure
to
do
so
may
cause
damage
to
the
heater.
5.
There
is
a
wire
mesh
filter
within
the
cold
inlet
to
trap
debris
from
entering
your
heater.
This
will
need
to
be
cleaned
periodically
to
maintain
flow.
Based
on
Energy
Content
of
1000BTU/Cubic
Ft:
Divide
each
appliance’s
BTU
requirement
by
1000BTU
to
get
the
appliances
Cubic
Ft.
requirement.
Takagi
into
account
the
distance
the
appliance
is
from
the
gas
meter,
look
in
the
above
gas
chart
to
properly
size
the
line.
For
sections
of
the
gas
line
supplying
gas
to
more
than
one
appliance
(Ex:
Point
A
to
Point
B),
add
up
the
cubic
ft.
requirements
of
the
appliances
that
are
being
supplied
by
that
section,
and
size
to
the
farthest
appliance.
For
Example:
The
section
from
A
to
B
supplies
gas
to
the
furnace,
range,
and
dryer.
Adding
up
the
BTU
requirements
and
dividing
by
1000
yields
a
cubic
ft.
requirement
of
220
cubic
ft.
of
gas.
The
farthest
appliance
is
the
range,
which
is
50
ft.
away
from
the
meter.
Looking
at
the
above
chart,
and
under
the
column
of
50ft.,
Section
A
to
B
needs
to
be
1”
in
order
to
supply
220
cubic
ft.
Do
not
reverse
the
hot
outlet
and
cold
inlet
connections
to
the
T
‐
H2
‐
DV/T
‐
H2
‐
OS
Water
Heater.
This
will
not
properly
active
the
water
heater.
FOR
YOUR
SAFETY,
READ
BEFORE
OPERATING:
10’
Length
1”
Pipe
Size
C
Gas
Sizing
Example
(Natural
Gas)
10’
Length
3/4”
Pipe
Size
15’
Length
1/2”
Pipe
Size
10’
Length
1/2”
Pipe
Size
Furnace
120,000BTU
T
‐
H2
‐
DV/
T
‐
H2
‐
OS
199,000BTU
5’
Length
1
‐
1/4”
Pipe
Size
Range
65,000BTU
10’
Length
3/4”
Pipe
Size
Dryer
35,000BTU
15’
Length
1”
Pipe
Size
5’
Length
1
‐
1/4”
Pipe
Size
Gas
Meter
B
A
CAUTION
Condensate drain
port
Water
outlet
(HOT)
Water
inlet
(COLD)
GAS inlet
