40
Giant
Manual
Hybrid
Tank
‐
Tankless
Flush
Procedure
Use
the
following
procedure
to
fl
ush
the
heat
exchanger
of
lime
or
scale
build
up.
Damage
caused
by
lime
build
‐
up
is
not
covered
by
the
unit’s
warranty.
A er
fl
ushing,
reset
any
error
codes
by
turning
o
ff
the
power
to
the
unit
and
turning
the
power
back
on.
H2
H3
H1
5
gallon
pail
of
virgin,
food
grade,
white
vinegar
(or
virgin,
food
grade,
citric
DRAIN
PUMP
1
2
COLD
WATER
SUPPLY
VALVE
HOT
WATER
VALVE
IN
‐
LINE
FILTER
10.Turn
o
ff
pump.
11.Rinse
the
cleaning
solu on
from
the
water
heater
as
follows:
a.
Disconnect
hose
(H1)
from
the
engine.
b.
Connect
a
cold
water
supply
fi
ng
and
hose
to
the
IN
‐
LINE
FILTER
fi
ng
at
the
base
of
the
engine
(3/4”
NPT).
c.
Move
drain
hose
(H3)
from
the
pail
to
a
drain.
d.
Open
cold
water
supply
and
allow
water
to
fl
ow
through
the
engine
for
5
minutes.
e.
Remove,
clean
and
replace
the
in
‐
line
fi
lter.
f.
Remove
Hose
(H3)
and
the
cold
water
sup
‐
ply
hose
from
the
base
of
the
engine.
g.
Re
‐
Install
the
(3/4”
NPT)
fl
ex
fi
ngs
and
to
the
assembly.
h.
CLOSE
THE
DRAIN
VALVE
i.
Open
the
cold
water
supply
valve
un l
wa
‐
ter
fl
ows
from
the
hot
water
fi
xture
j.
Close
the
cold
water
supply
valve.
k.
Connect
power
to
the
water
heater
and
turn
the
temperature
down
to
set
point
1.
12.Open
the
cold
water
supply
valve
un l
water
fl
ows
from
the
hot
water
fi
xture
(See
Step
2).
13.Close
the
hot
water
fi
xture
and
inspect
the
appliance
and
plumbing
for
leaks.
1
2
Do
not
con nue
un l
all
water
has
drained
from
the
tank.
NOTICE
1.Disconnect
electrical
power
to
the
water
heater.
2.CLOSE
the
cold
water
supply
valve.
Leave
the
hot
water
valve
and
a
hot
water
fi
xture
OPEN
to
remove
pressure
from
the
system.
3.Connect
one
end
of
a
hose
to
the
drain
valve
on
the
tank
and
direct
the
other
end
to
a
drain.
OPEN
the
drain
valve.
4.Remove
the
(3/4”
NPT)
fl
ex
fi
ngs
and
from
the
assembly.
(Note:
The
tankless
unit
will
s ll
contain
approximately
1/2
gallon
(1.9
L)
of
water.
Prepare
a
bucket
to
catch
this
water.)
5.Connect
pump
outlet
hose
(H1)
to
the
(3/4”
NPT)
in
‐
line
fi
lter
fi
ng
at
the
base
of
the
engine.
6.Connect
drain
hose
(H3)
to
the
(3/4”
NPT)
supply
fi
ng
at
the
base
of
the
engine.
7.Pour
approximately
4
gallons
(15.2
L)
of
virgin,
food
grade,
white
vinegar
or
citric
acid
into
a
pail.
8.Place
the
drain
hose
(H3)
and
the
hose
(H2)
to
the
pump
inlet
into
the
cleaning
solu on.
9.Operate
the
pump
and
allow
the
cleaning
solu on
to
circulate
through
the
water
heater
for
at
least
45
minutes.
2
1
