Troubleshooting
Guide
8|
Page
5.2
TROUBLESHOOTING
‐
GENERAL
PROBLEMS
Proceed
to
the
Error
Codes
section
if
an
error
code
is
identified.
For
other
common
problems
that
do
not
involve
an
error
code,
see
if
the
following
items
help:
The
water
is
not
hot
enough.
The
water
is
too
hot.
Temperature
fluctuates
when
a
fixture
is
opened.
Unit
does
not
ignite
when
water
goes
through
it.
It
takes
a
long
time
to
get
hot
water
at
the
fixtures.
The
fan
motor
is
still
spinning
after
operation
has
stopped.
Abnormal
sounds
come
from
the
unit.
Loss
of
pressure
at
all
sinks
when
the
dishwasher
fills.
Unit
has
power,
gas,
and
water
but
does
not
turn
on.
Multiple
Heater
Setup
(Easy
‐
Link)
THE
WATER
IS
NOT
HOT
ENOUGH
•
Compare
the
flow
and
temperature
at
the
pressure
relief
valve.
o
If
the
temperature
and
flow
rate
are
correct
at
the
PRV
then
the
problem
resides
in
the
plumbing
line,
not
in
the
tankless
unit.
Check
for
a
cross
connection
or
other
water
line
problems
•
Test
the
hot
water
temperature
with
a
handheld
thermometer
to
measure
how
far
off
the
water
temperature
is
from
the
set
temperature.
o
The
set
temperature
may
be
set
too
low.
The
temperature
can
be
changed
with
the
pushbuttons
on
the
PCB
or
by
the
remote
temperature
controller,
if
one
is
installed.
•
Check
for
cross
plumbing
between
cold
water
lines
and
hot
water
lines.
See
the
Procedures
section
(p.
21)
for
instructions.
•
Unit
may
be
hard
water
scaled.
The
scale
acts
as
an
insulator
preventing
the
heat
exchanger
from
transferring
heat
to
the
water.
Contact
a
Takagi
Service
Agent.
•
The
unit
may
not
be
receiving
enough
gas.
o
The
gas
supply
valve
may
not
be
fully
open.
o
The
gas
line
may
be
sized
improperly.
o
The
gas
supply
pressure
may
be
too
low.
This
may
be
caused
by
a
malfunctioning
gas
supply
regulator,
so
check
to
see
if
your
regulator
is
working
properly.
•
Check
to
see
that
a
check
valve
is
installed
between
the
pump
discharge
and
the
connection
to
the
cold
water
supply.
Inspect
the
check
valve
for
proper
operation.
If
there
isn’t
one
installed,
or
if
it
is
malfunctioning,
cold
water
may
be
back
‐
feeding
into
the
system.
•
Double
‐
check
for
a
101
error
code.
A
101
error
code
will
reduce
the
amount
of
gas
input
into
the
heater.
•
Output
temperature
will
be
affected
if
air
flow
is
impeded.
o
Check
construction
dust
and
debris
in
venting,
such
as
dry
wall.
o
If
there
is
dust
inside
the
cabinet,
there
will
also
be
dust
inside
the
burner
and
heat
exchanger.
See
the
procedure
for
cleaning
the
burner
(p.
26).
THE
WATER
IS
TOO
HOT
•
The
set
temperature
may
be
set
too
high.
The
temperature
can
be
changed
with
dipswitches
on
the
PCB
or
by
the
remote
temperature
controller,
if
one
is
installed.
