Specifications

14
NOTE
Make sure yellow thermocouple lead wire is connected to terminal #9 on back of the
controller.
Make sure red thermocouple lead wire is connected to terminal #10 on back of the controller.
Make sure the exposed section of the T/C lead wires are not contacting each other.
Muffle (Heating Element) Replacement
a. Disconnect from power supply.
b. Set furnace on its door.
c. Remove (one piece) top, back and bottom cover.
d. Disconnect element lead wires from door switch. (Note placement and connection of wires to door
switch.)
e. Remove clip from thermocouple and pull thermocouple out of muffle.
f. Remove metal retaining band from defective muffle.
g. Loosen top adjustment bracket and remove defective muffle.
h. Insert new muffle with vent hole facing the top of unit.
i. Readjust top bracket to fit snugly up against muffle. Make sure muffle is laying flush against front
case section.
j. Reinstall metal retaining band and tighten until muffle seats firmly into case section.
k. Reconnect element lead wires to door switch.
On the 120V or 100V muffle there are three element lead wires. Connect the top and the
bottom element lead wire to the top terminal connector on the door switch. Connect the middle
element lead wire to the bottom terminal connection on door switch.
On the 230V and 240V muffles there are two element lead wires. Connect the top element
lead wire to the top terminal connector on door switch. Connect the bottom element lead wire to
bottom terminal connector on the door switch.
NOTE
Make sure the black insulation sleeving covers the exposed portion of the element lead
wires.
l. Reinstall the thermocouple and the retaining clip.
NOTE
Make sure the exposed section of the T/C lead wires are not contacting each other.
m. Reinstall the cover section.
n. Set the furnace upright and test the operation of the furnace.