3-FLASH
Goodman · GMSS920804CN 80,000 BTU 92% AFUE Single-Stage Gas Furnace
The draft inducer motor is running but the pressure switch has not closed within the expected time window — one of the most common Goodman furnace faults; causes include blocked exhaust vent (ice, bird nests, debris), clogged condensate drain (backs up into inducer housing), cracked or kinked pressure switch hose, weak or failing inducer motor, or a failed pressure switch
Error 3-FLASH on the Goodman GMSS920804CN 80,000 BTU 92% AFUE Single-Stage Gas Furnace means: Pressure Switch Did Not Close. The top-ranked community fix is “Test and Replace Pressure Switch or Inducer Motor” (hard difficulty, ~60 min, DIY cost: $20-$40). 2 community-ranked fixes available below.
Published February 2026 · 2 fixes · furnace
Content is based on manufacturer service documentation, community repair experience, and OEM technical bulletins. Always verify with your owner's manual.Learn about our editorial standards.
While many furnace repairs can be done safely at home, consider hiring a qualified technician if:
Average professional repair cost for this issue: $200-$400.
Incorrect Blower Speed / DIP Switch Configuration
System Lockout — Retry Limit Exceeded
Pressure Switch Stuck Closed
High Limit Switch Open
Flame Sensed Without Gas Valve Call
Flame Lost During Operation
Ignition Lockout — Failed to Ignite
Igniter Circuit Fault
The Goodman GMSS920804CN 80,000 BTU 92% AFUE Single-Stage Gas Furnace has 8 other known error codes:
Error code 3-FLASH also appears on 2 other Goodman models:
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