Goodman furnace flash codes (3 blinks and more)
Reviewed 3 primary sourcesSee sources
Flash codes depend on the furnace’s control board, so start with the model number on the rating plate. On GMSS96 and GCSS96 furnaces, three flashes means the pressure switch is stuck open: the furnace didn’t prove that its venting is clear, so it won’t light. Finding why is a technician’s job.
Applies to: Goodman GMSS96 and Amana-built GCSS96 single-stage gas furnaces (specification sheet SS-GMSS96, wiring diagram 0140F01908-A), Goodman GMH, AMH, GCH and GDH furnaces with the “H” control board (eight-flash code only, from service bulletin SF-024)
How to read the code
The flash legend is printed on the furnace’s wiring diagram. The GMSS96 control also keeps a history of fault codes that it shows through the same LED.[1]
GMSS96 and GCSS96 single-stage furnaces (wiring diagram 0140F01908-A)
| Code | What it means | What an owner can check |
|---|---|---|
| Steady on | Normal operation.[1] | Nothing to do. |
| Off | Control failure.[1] | No owner check is given; call a qualified technician. |
| 1 flash | System lockout: the furnace used up its ignition retries.[1] | No owner check is given; call a qualified technician. |
| 2 flashes | Pressure switch stuck closed.[1] | No owner check is given; call a qualified technician. |
| 3 flashes | Pressure switch stuck open (it didn’t close).[1] | No owner check is given; call a qualified technician. |
| 4 flashes | Open high limit.[1] | No owner check is given; call a qualified technician. |
| 5 flashes | Flame sensed without the gas valve open.[1] | No owner check is given; call a qualified technician. |
| 6 flashes | Open rollout switch.[1] | No owner check is given; call a qualified technician. |
| 7 flashes | Low flame signal.[1] | No owner check is given; call a qualified technician. |
| 8 flashes | Check the igniter or improper grounding.[1] | No owner check is given; call a qualified technician. |
| Continuous rapid flashing | Reversed 115-volt polarity.[1] | No owner check is given; call a qualified technician. |
Goodman “H” model furnaces: GMH, AMH, GCH and GDH (service bulletin SF-024)
| Code | What it means | What an owner can check |
|---|---|---|
| 8 flashes | Igniter relay fault or a shorted hot-surface igniter; in the field, most often missing or poor grounding.[2] | No owner check is given; call a qualified technician. |
For a pressure switch that won’t close, Goodman’s troubleshooting chart for its 80% furnaces lists what a technician checks: a blocked, pinched or misconnected pressure-switch hose, a blocked flue or intake pipe, a blocked drain, a weak draft inducer, the switch itself and loose wiring. That chart is for a different furnace family, so treat it as general guidance.[3]
Sources
Facts on this page are restated in our own words from the manufacturer and government documents below. Formats and codes change between product lines, so check the document for your exact model.
- GMSS96 / GCSS96 Single-Stage Gas Furnace specification sheetGoodman Manufacturing Company, L.P. · SS-GMSS96 (10/19, supersedes 9/18); wiring diagram 0140F01908-A · Page 10, wiring diagram LED legend (same legend on page 10 of the 8/15 edition) · retrieved
- Service Bulletin SF-024: Eight-flash fault codeGoodman Technical Services · SF-024 (November 3, 2008) · Whole bulletin (1 page) · retrieved
- Service and Troubleshooting: 80% Single Stage Gas Furnaces (GM9S80 family)Daikin Comfort Technologies Manufacturing, L.P. · RS6621008r2 (©2019-2023) · Front warning box; 'Scheduled Maintenance' (p. 8); '1 Stage Troubleshooting Codes' chart (p. 31); Error Code E1/E2 flowchart (p. 36) · retrieved
Primary publishers: Goodman Manufacturing Company, L.P., Goodman Technical Services, Daikin Comfort Technologies Manufacturing, L.P.. Spotted an error? Email the address in the footer with the model and the document you are using.