Specifications
MONITOR HEATING SYSTEMS
Section
1:
Description
1-26
SOLENOID
PUMP
The
Solenoid Pump, mounted
on the
Fuel
Constant
Level
Valve,
and
controlled
by a
microprocessor,
delivers
four
fuel flow modes (High, Medium-High,
Medium-Low,
Low)
to the
Burner Pot.
1-27
ELECTRICAL
SYSTEM
Electrical
power
is
supplied
to the
Monitor
to run the
Microprocessor
and the
other
electrically-energized
component.
Electrical operation
of the
Monitor
can be
thought
of
as
having
the
following
eight(8)
distinct
phases.plug
in;
turn-on;
pre-purge/pre-heat;
ignition; pre-
combustion;
heating;
Shutdown
and
post-purge.
All
electronic diagrams, Such
as
wiring diagram,
circuit
board layout,
and
electrical
schematic
can be
found
in
Section
7 of
this Service Manual.
1-28
MICROPROCESSOR
Principally consisting
of a
64-pin
Integrated
Circuit,
the
Microprocessor provides safety timings, controls
relays
and
provides
clock
and
thermostat functions
for
the
Monitor heater.
A
component layout
of the
Printed
Circuit Board
is
found
in
Section
7 of
this
Service
Manual.
1-29
TEMPERATURE
SENSOR
The
sensor
which
is
capable
of
sensing
room
tem-
perature
within
a
range
of
42"F
to
96°F,
can be
left
mounted
on the
back
of the
heater cabinet
or be
wall mounted.
Approximately
4/^'(about
140 cm) of No. 22 AWG
Wire
is
supplied with
the
sensor
to
facilitate wall
mounting
the
sensor
in a
favorable location.
1-30
SAFETY
MECHANISMS
Several
safety mechanisms have been built into
the
Monitor
Heating System. These devices protect
the
user
against personal
injury,
protect
the
heater
against
damage,
and
shutdown
the
heater
if a
malfunction occurs.
During
installation make
sure
that
all
Exhaust
Lines
are
tight.
Do not
operate
the
heater
without
the
insulating covers.
1-32
AIR
CIRCULATION
FAN
GUARD
This guard
is an
integral
part
of the fan
assembly.
The
guard protects
the
user
against physical injury
which could occur
from
accidental contact with
revolving
metal
fan
blade.
1-33
FUSE
2-amp.
and
10-amp.,
125VAC,
fuses protect
the
heater
from
damage resulting
from
power overloads.
In
the
event
of a
power surge
or
internal wiring
hazards,
the
fuse
opens
and
power
to the
heater
is
cut
off.
The
electrical outlet into which
the
heater
is
con-
nected should
be
protected
by at
least
a
15-amp.
fuse
or
circuit breaker.
1-34
OVERHEAT PROTECTOR
SWITCHES
(M-2400)
Connected
in
series,
two (2)
normally-closed Over-
heat
Protector Switches safeguard
the
heaters
against damage
due to
overheating.
The
switches
are
rated
115'C
(239'F).
Should
a
Monitor overheat (internal temperatures
rise
beyond
115'C
(239'F)). either
or
both switches will open
to
shut down
the
heater.
After
extinguishing
the
flame,
the
code
FE14J
is
indicated
in the
digital display.
The
Overheat Protector Switches
will
automatically
reset
after
cooling down.
Once
the
heater
has
cooled
to
90'C
(194*F),
the
system
can be
restarted.
To
restart
the
Monitor,
proceed
as
follows:
A.
Press ON/OFF Switch
to
OFF.
B.
Allow heater
to
cool.
C.
Troubleshoot
the
cause
of the
overheat.
D.
Press
ON/OFF switch
to ON
E.
Proceed with normal operation.
1-31
CLOTH COVERED EXHAUST
PIPE
Insulating cloth covers
are to be
placed
over
all
metal surfaces
of the
Exhaust
Line
during
installa-
tion.
Since
combustion by-products
are
vented
at
ele-
vated
temperatures,
the
Exhaust Pipe will become
hot
during operation.
The
insulating
cloth
covers
protect
the
user from burn hazards associated with
accidental contact with these heated metal sur-
faces.
6