Much less exhaust steam - Carrier 58MTA 80,000 BTU

Options

Noticed suddenly far less steam out the exhaust. Cleaned Blower, new capacitor, new limit switch on burner box…no improvement. I opened up inducer assembly and cleaned flat disc impeller & all vacuum ports and lines. Pressure switches operating as should.

Tried new control board- same results. I snaked both the intake and exhaust- no clogs.

When it was running, I "helped" the intake with aiming shopvac (on the blowing side) at the intake and steam started rolling.

Is it possible bad windings on inducer motor that is enough to close pressure switches but not enough RPM to vent properly? OR… is it more likely a bad secondary heat exchanger? I tried the long match in the primary with blower running and there was no dancing flame.

Just need the best suggestion (if I can avoid buying a new furnace). Thanks!!!

Comments