Introduction: Hardin-F-180 Furnace Thermocouple Replacement
How I figured out how to replace the thermocouple on a Hardin 180 furnace.
Step 1: Removal of Mesh Gaurd
Remove the 6 screws with washers holding mesh Heat guard in place. Ceramic cones may or may not stay in place.
Step 2: Lid Assembly
Remove 4 screws on back holding lid assembly to furnace body. Set aside.
Step 3: Access Plate
Turn oven assembly upside down and remove the 4 screws holding it in place
Step 4: Removal of Thermal Couple
Remove the 2 screws holding coupler to body.
Step 5: Temperature Control Panel
Loosen screws from back of control panel where thermocouple is connected to. ( keep in mind the proper placement colors of the wires)
Step 6: Swapping Out Coupler
Pull old out and place in new.
Step 7: Reattach Thermocouple
Reattach thermocouple to body and reattach wires to back of control panel. Zip tie loose wire to the rest of the wires.
Step 8: Reattach the Rest
Reattach access panel, lid assembly, and mesh guard. In that order.
Step 9: Test
Turn on. Run in 3 wave.
1st- 400 C;
COOL ;
2nd-800 C;
COOL;
3rd-1150 C
Never leave unattended.

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3 Comments
7 years ago on Introduction
That is some very useful information. Thanks for sharing.
Reply 6 years ago
Noticed this post after I googled hardin furnace while I was searching for a manual to the installed PID. Have come up empty on a manual of any sort. Since you built this was wondering if you had some info on modifying of changing the settings of the factory installed PID controller for this furnace?
Reply 6 years ago
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