What does 41 mean?
Inducer motor running but pressure switch did not close. Possible blockage in vent or switch failure.
Common causes
- Blocked condensate drain
- Clogged inducer wheel
- Failed pressure switch
- Cracked or pinched pressure switch hose
- Blocked flue vent pipe
Diagnostic & testing steps
- 1. Check and clear condensate drain line
- 2. Remove pressure switch hose and verify no blockage
- 3. Test pressure switch: apply suction - should click closed
- 4. Check inducer motor wheel for debris buildup
- 5. Verify vent pipe has no blockages
Tools required
- Multimeter
- Manometer
- Shop vac
OEM parts & part numbers
Pressure Switch, Condensate Drain Assembly, Inducer Motor
Part numbers: HK06WC069, CHPF4860D6, HC21ZE118
Safety warning
⚠️ Never short out the pressure switch — it is a safety device protecting against combustion gases.
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