On a Carrier Furnace model #58STX110-14122, when the initial call for heat comes on, everything works just fine in the following order:
- Thermostat sends a call for heat
- Draft Inducer motor kicks on
- The Hot Surface Igniter stick warms up
- Gas flow begins and burners light up
- After a short delay, the blower fan runs and hot air comes through the outlet registers
Now, after the thermostat temperature is realized, the system turns off (fan is in auto) and when the next call for heat comes on, all of the above steps happen except for the last one – where the blower fan does start spinning and instead produces a groaning sound. Attempts to prod it with a wooden stick do not work either. It seems stuck in place. This lack of airflow causes the system to throw error code #33 – LIMIT CIRCUIT FAULT, which turns into lockout #13 – LIMIT CIRCUIT LOCKOUT since the blower doesn't turn on.
I tried replacing the oval shaped 'motor run capacitor', but the system still exhibits the same behavior as above. Resetting the system and turning it on will get the system working properly for the first time as above.
Any pointers are appreciated as I am at my wits' end here!!
Best Answer
Turned out it was a bad blower motor. Replacing it was the solution.