During Operation - Kenmore K90-150 Owner's Manual

SAFETY SEQUENCES DURING OPERATION
DRAFT INDUCER TEMPERATURE SAFETY SWITCH
IF DRAFT INDUCER TEMPERATURE REACHES
TEMPERATURE SAFETY SWITCH SETPOINT,
SAFETY SWITCH CONTACTS OPEN IMMEDIATEL_
CLOSING GAS VALVE (LIGHT GOES OUT).
POST PURGE AND SWITCHES OFF.
C,ROOLATOR RUNS , . HA RMOSTAT ON C ALL
WHEN TEMPERATURE SAFETY SWITCH CONTACTS
REMAKE BEFORE END OF CALL FOR HEAT, CON-
TROL GOES INTO NORMAL LIGHT-OFF SEQUENCE.
LOSS OF FLAME SIGNAL
IF AN ESTABLISHED FLAME SIGNAL IS LOST WHILE
CONTROL EXPECTS THAT THE BURNER IS OPERAT-
ING, CONTROL WILL IMMEDIATELY DE-ENERGIZE
GAS VALVE. VALVE AND FLAME MGHTS GO OUT.
I DRAFT INDUCER RUNS THROUGH 30 SECOND
POST PURGE. I
CONTROL WILL ATTEMPT TO RELIGHT BOILER
3 TIMES. IF FLAME IS NOT PROVEN, CONTROL
LOCKOUT - PROBLEM ESTABLISHING A FLAME
SIGNAL. VALVE LIGHT IS BLINKING.
LOSS OF COMBUSTION AIRFLOW
IF COMBUSTION AIRFLOW IS LOST WHILE BURNER
IS FIRING (DIFFERENTIALAIR PRESSURE SWITCH
CONTACTS OPEN) GAS VALVE WILL BE DE-ENER-
GIZED. VALVE AND FLAME LIGHTS GO OUT.
UTES FOR AIRFLOW TO BE RE-ESTABLISHED.
iF AIRFLOW DOES NOT RE-ESTABLISH CONTROL I
I LOCKOUT- PROBLEM WITH COMBUSTION AIR-
[ FLOW. PURGE L GHT BL NKS.
CASTING TEMPERATURE SAFETY SWITCH
IF BURNER OPERATES WHEN BOILER HAS NO WA- i
ER, ALUMINUM BOILER SECTIONS HEAT UP RAPIDLY. I
÷
CASTING TEMPERATURE SAFETY SWITCH CON-
TACTS WILL OPEN, BREAKING 24 VOLT POWER
TO IBC. POWER INDICATOR LIGHT GOES OUT.
REQUIRES MANUAL RESET TO RECLOSE CON-
TACTS. POWER LIGHT GOES OUT.
HIGH LIMIT CONTROL
IF BOILER WATER TEMPERATURE REACHES
HIGH LIMIT (AQUASTAT) SETPOINT, HIGH LIMIT
N.C. CONTACTS OPEN IMMEDIATELY, CLOSING
GAS VALVE. VALVE AND FLAME LIGHTS GO OUT.
SECOND POST PURGE AND SWITCH OFF.
÷
WHEN HIGH LIMIT CONTACTS REMAKE BEFORE
END OF CALL FOR HEAT- CONTROL GOES INTO
A NORMAL LIGHT-OFF SEQUENCE.
CIRCULATOR PUMP
CIRCULATOR WILL BE ENERGIZED AS LONG AS
THERMOSTAT CALLS FOR HEAT DUR NG LOCKOUT.
÷
RECOVERY FROM ANY LOCKOUT REQUIRES
RESET, WHICH IS ACCOMPLISHED BY REMOVING
AND REAPPLYING THE THERMOSTAT CALL FOR
HEAT OR POWER TO CONTROL.