PAGE 15 of 61 HO-7-1237 & HO-4-1234 OIL-FIRED HEATERS
© SAMUEL JACKSON, INCORPORATED 2003 ALL RIGHTS RESERVED
ERROR 432 *
ATOMIZING AIR PRESSURE SWITCH NOT WORKING:
The Atomizing Air Pressure
Switch (AAP) told the PLC that air pressure was present although the air valve had not
been opened. Check for a leaking air valve, defective AAP, or a bridged circuit in the
AAP.
ERROR 433
MODULATING MOTOR FAILS TO GO TO CLOSE:
There is a limit switch indicating
when the burner is in the low fire position. The PLC demands that this switch be ON in
the low fire position and OFF as the valve opens. If burner throttle is in the low fire
position, check low fire switch adjustment. If low fire position is not attained, run the test
program to Step 6 and test the operation of the Modulating Motor (MM). Check for
proper voltage on terminals L1 and L2 of MM.
ERROR 434
*
MODULATING MOTOR FAILS TO OPEN:
This is similar to ERROR 433, and the same
things should be checked.
ERROR 435
LOW COMBUSTION AIR PRESSURE:
This error occurs when the Combustion Air
Pressure Switch (CAP) senses insufficient combustion air pressure (less than 1 inch w.c.)
during certain steps of the operating program. Check for proper rotation of the
combustion air fan motor FM, and make sure the overload relay MOL1 for this motor is
not tripped. Reset MOL1 if tripped. After verifying good combustion air pressure
(through the tubes going to CAP), check for proper operation of CAP.
ERROR 436
COMBUSTION AIR PRESSURE SWITCH FAILED:
The combustion air fan is killed
prior to trial for ignition. The pressure must fall to 1 inch w.c. (25 mm) and turn off
Combustion Air Pressure Switch (CAP) within 15 seconds or this error will be activated.
Look for wrong adjustment of CAP or bridging of its contacts. See Step 9 in the test
program.
ERROR 441
FAN INTERLOCK HAS BEEN BYPASSED:
Samuel Jackson Heaters are provided with a
fan interlock to provide immediate shutdown of the heater when the fans are turned off.
This error indicates that an electrical signal is being received through the fan interlock
with no airflow present, effectively bypassing this important safety feature.
