L404A
D
F

L604A

L
M
INSTALLATION
Mounting
ona
Boiler
If
it
is
not
convenient
to
mount
the
controller

alongside

the
pressure
gauge
install
a
steam
trap
siphon
loop
in
the
fitting

provided

by
the
boiler
manufactUrer
If
thereis
no
fitting
mount
the
steam
trap
at
a
location
recommended
by
the
boiler
manufacturer
Screw
the
controller

directly

to
the
steam
trap
and
level
the
controller
Mounting
at
a
Remote
Location
If
there
is excessive vibration at
the
boiler
that
can

adversely

affect
the
operation
of
the
controller
mount
the
controller
at
a
remote
location
All
piping
from
the
boiler
must
be
suitable
and

solidly

mounted
The
piping
must
be
properly

pitched

to
drain
all
condensation
back
to
the
boiler
A
steam
trap
siphon
loop
must
be
mounted
be
tween
the
remote
piping
and
the
controller
Level
the
controller
after
installation

Supervision

of

Atomizing

Medium
Pressure
Air
or
Steam
L404B
When
air
or
steam
isused
as
an

atomizing

medium
in
an
oil
burner
system
authorities

having

jurisdiction

approval

bodies
and
codes
often

require

a
low
limit
to
prevent

opening

the
main
oil
valve
until
sufficient

atomizing

pres
sure
is
present
and
to
shut
down
the
system
when
the

atomizing

pressure
falls
too
low
The
L404B
is
recommended
for
this

application

It
makes
a
circuit
when
thepressure
rises
to
the
set
point
and
breaks
when
the pressure
falls
to
the
set
point
minus
the
differential
Fig
10
WlRING
1

DiscoDDe

t
the
power

supply

before

beginning

wiring
to

preventelectrical

shock
or

equipment

damage
2
Assume
all
wiring

complies

with

applicable

electrical
co
ordinances
and

regulations

Use
NEC
Class 1

line

voltage

wiring

3
Fornormalinstallations
use
moisture
resistant
No
14
wire
sUitable
for
at
least

1670

1

750C

when
you
are
using
the
controller
with
a
flame

safeguard

primary

control
or
at
least
1940F

900C

when
using
it
with
a

programming

control
4
For

high

temperature
installations
use
moisture
resis
tant
No
14
wire
selected
for
a
temperature

rating

above
the
maximum
operating
temperature
5
All
models
have
a
terminal
block
inside
the
cover
Fig
3
and
4
and
a
78
in
22
2
mm
hole
in
one
side
for
1
2
in
condui
cable
or
wires
Remove
the
front
cover
by
loosen

ing tIi

e
screw
at
the
bottom
of
the
main
scale
6
Refer
to
Fig
5
through
9
for

typical

hookups

Follow
the
burner
or
boiler
manufacturer
s

wiring

diagram

if
pro
vided
7
Make
sure
the
loads
do
not
exceedthe
Switch
Contact

Ratings

in
the

Specifications

section
8

Replace

the
front
cover
when
wiring
is

completed

Fig
3
L404
terminal
blocks
and
internal
schematics
RISE
L404AC
L404B
D
BREAKS
ON
PRESSURERISE
TO
SETPOINT
MAKE ON
PRESSURE
RISE
TO
SETPOINT
RISE
B
L404F
SNAPACTING
BREAKS
R
a
MAKES
R
WON
PRESSURE
RISE
TO
SETPOINT
M8941
Fig
4
L404
terminal
block
and
Internal
schematic
L604A
L604L
M
MAKES
Rl
W
BREAKS
R2
8
ON
PRESSURERISE
TO
SETPOINT
SPDT
SWITCH
ACTION
WITH
JUMPER
INSTALLED
M8935
OTHERWISE
TWO
ISOLATED
SPSTSWITCHES
Fig
S
L404used
as
a
limit
or
as
an
operating
controller
SPST
CONTROLLER
Ll
HOT
POWER

1

SUPPLY
Lll
U
FlAME
SAFEGUARD
CONTROL
MOTOR
OR
OTHER
LOAD
PROVIDE
DISCONNECT
MEANS
AND
OVERLOAD
PROTECTION
AS
REQUIRED
HIGH
UMIT
l
404A
OR
C
BREAKS
WHEN
PRESSURE
RISES
TO
SETPOINT
LOW
UMIT
t
4048
BREAKSWHEN
PRESSURE
FALLS
TO
SETPOINT
MINUS
DIFFERENTIAL
OPERATING
CONTROLLER
t
404A
BREAKS
WHEN
PRESSURE
RISES
TO
SETPOINT AND
MAKES
AGAINWHEN
PRESSURE
FALLS
TO
SETPOINT
MINUS
DIFFERENTIAL
M8936