Steffes DLF40B - Manual (Page 34)

Troubleshooting Information
(cont'd)
33
B. PROBLEM: FURNACE WILL NOT CHARGE (FURNACE HAS NO CORE CHARGE) continued...
Check for 24 VAC
across L1 and L2 on the
auxiliary control board.
Verify polarity of the red and yellow
thermocouple wires connected to the
auxiliary control board. Red should be
connected to "TC­" and yellow should
be connected to "TC+".
Check unit wiring.
24 VAC No Voltage
Jump "TC­" and "TC+"
terminals on auxiliary
control board.
Fix wiring.
Incorrect
Ok
Charge
Light "ON"
Check continuity across
the red and yellow
thermocouple wires.
Replace auxiliary
control relay board.
Charge
Light "OFF"
Replace the
thermocouple.
Contact
Steffes
Technical
Support.
No Continuity
Continuity
NOTE
This portion of the troubleshooting flow chart is to test operation of the auxilairy control board.
Furnaces built after January of 1998 were produced with this additional control. If a system built
before 1998 experiences element failure, Steffes recommends that the auxiliary control board be
added as a supplemental controller for monitoring core temperatures in systems which have ele­
ment failure.