SLOW-FLASH
Goodman · GMVC960804CN 96% AFUE 80,000 BTU Two-Stage Gas Furnace
The LED is flashing slowly (~1 Hz continuous) — the system is in a timed lockout or startup delay period; wait for the delay to expire; if it persists, look for a counted flash pattern indicating a specific fault code
Error SLOW-FLASH on the Goodman GMVC960804CN 96% AFUE 80,000 BTU Two-Stage Gas Furnace means: System in Delay / Timed Lockout. The top-ranked community fix is “Diagnose and Clear Underlying Fault Causing Lockout” (hard difficulty, ~90 min, DIY cost: $0-$20). 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: $150-$300.
Incorrect Blower Speed / DIP Switch Configuration
System Lockout — Retry Limit Exceeded
Pressure Switch Stuck Closed
Pressure Switch Did Not Close
High Limit Switch Open
Flame Sensed Without Gas Valve Call
Flame Lost During Operation
Ignition Lockout — Failed to Ignite
The Goodman GMVC960804CN 96% AFUE 80,000 BTU Two-Stage Gas Furnace has 8 other known error codes:
Error code SLOW-FLASH also appears on 2 other Goodman models:
Ad Space — banner
Replace ADSENSE_PUBLISHER_ID in AdUnit.tsx