ECR International Olsen Q90 125-200 II Series Installation, Operation & Maintenance Manual page 25

DRAFT INDUCER TEMPERATURE SAFETY
SWITCH
If draft inducer temperature reaches temperature
safety switch set-point, safety switch contacts open
immediately, closing gas valve
Draft inducer runs through 30 second post purge and
switches OFF.
Circulator runs with thermostat on call for heat.
When temperature safety switch contacts connect
before end of call for heat, control goes in normal
light-off sequence.
LOSS OF FLAME SIGNAL
If established fl ame signal is lost while control expects
burner is operating, control immediately de-energizes
gas valve.
Valve and fl ame lights go out.
Draft inducer runs through 30 second post purge.
Control attempts to light boiler 3 times. If fl ame is not
proven, control lockout problem establishing fl ame
signal.
Valve light is blinking
Control automatically resets after 1 hour.
LOSS OF COMBUSTION AIRFLOW
If combustion airfl ow is lost while burner is fi ring
(Differential air pressure switch contacts open) gas
valve is de-energized.
Valve and fl ame lights go out.
Draft inducer runs through 30 second post purge.
If call for heat remains, IBC waits 5 minutes for airfl ow
to be re-established.
If airfl ow does not re-establish control lockout problem
with combustion airfl ow.
Purge light blinks
Control automatically reset after 15 minutes.
11 - DETAILED SEQUENCE OF OPERATION
(light goes out) .
.
.
CASTING TEMPERATURE SAFETY SWITCH
If burner operates when boiler has no water,
aluminum boiler sections heat up rapidly.
Casting temperature safety switch contacts will
open, breaking 24 volt power to IBC.
Power indicator light goes out.
Requires manual reset to re-close contacts.
Power light goes out.
HIGH LIMIT CONTROL
If boiler water temperature reaches high
limit setpoint, high limit n.c. contacts open
immediately, closing gas valve.
Valve and fl ame lights go out.
Draft inducer continues to run for 30 second post
purge and switch OFF.
Circulator runs as long as thermostat calls for
When high limit contacts connect before end of
call for heat - control goes into normal light-off
CIRCULATOR PUMP
Circulator is energized as long as thermostat calls
for heat during lockout.
Recovery from any lockout requires reset, which
can be accomplished by:
(a) Removing and re-establishing thermostat's
call for heat or turning service switch off
(b) Waiting for control to automatically reset after
15 minutes for loss of combustion airfl ow or one
hour for loss of fl ame.
25
heat.
sequence.
and back on;
or