Goodman furnace code EAF: lost communication with the R-32 sensor

Furnace control display or LED

EAF

“Furnace has lost communication with the R-32 sensor and the furnace is in mitigation mode.”

GR9S92 / GR9S96 / GD9S96, A/GR9S96*U* Ultra-Low NOx, GR9S80 / GD9S80 / AR9S80 / AD9S80, A/GR9S80*U* Ultra-Low NOx, VR9S80/VD9S80, GR9T96 / GD9T96 / AR9T96 / AD9T96, GR9T80 / GD9T80 / AR9T80 / AD9T80, GRVT96 / GDVT96 / ARVT96 / ADVT96, GRVT80 / GDVT80 / ARVT80 / ADVT80, GRVM97 / GDVM97 / ARVM97 / ADVM97, *RVS96*U & CDVS96*U; *RVS80*U, GMVC96*BB / GCVC96*BB · IOG-2037D p. 45; IOG-2040D p. 40; IOG-2035D p. 33; IOG-2039F p. 34; IOG-2050A p. 41; IOG-2038E p. 52; IOG-2036D p. 33; IOG-2044B p. 52; IOG-2043B p. 37; IOG-2045A p. 52; IOG-2042A p. 48; RS6612023R2 p. 44
Technician

What it means

EAF says the furnace has lost communication with its R-32 sensor and is in mitigation mode IOG-2037D, p. 45. Goodman’s tables describe what you notice: the furnace stops heating and only the fan runs RS6612301, p. 37. The same sensor reports a refrigerant leak as a different code, EAL, for which the table’s action is to investigate the indoor coil IOG-2037D, p. 45.

The current table gives two possible causes IOG-2037D, p. 45:

The furnace may not be paired with an R-32 cooling unit. The table refers to the R-32 Information Section of the installation instructions, which these pages do not cover.
The R-32 sensor wire is loose or damaged.

Its corrective actions are to verify that the wire connection to the R-32 sensor is not loose, verify that the sensor wire is not damaged, and replace the R-32 sensor if necessary IOG-2037D, p. 45.

EAF appears in the tables for the GR9, GD9 and VR9 series, the variable speed GRVT, GRVM and RVS lines, and, from its revision with the printed date November 2026, the GMVC96BB service manual RS6612023R2, p. 44. The full list of series is at the top of this page.

Check these first

No Goodman document gives an owner step for EAF. The owner’s manual has no code table and sends you to the installation instructions for code identification HIG-2002A, p. 8; the corrective actions there are written for the installer or technician.

Write the code down; for a flashing LED the owner’s manual asks you to record it HIG-2002A, p. 8.
Contact a qualified servicer HIG-2002A, p. 8.

The owner’s manual’s limits apply: “Do not attempt repairs yourself” HIG-2002A, p. 8, and “do not remove any internal compartment covers” HIG-2002A, p. 6. That manual is dated 09/19, and none of the passages these pages draw on says whether to shut the furnace down while it is in mitigation mode, so this page gives no shut-down step for EAF.

When to call a licensed technician

Whether the furnace is paired with an R-32 cooling unit. The control’s menu has A2L function settings that the service manual ties to its R-32 Information Section RS6612301, p. 34.
The R-32 sensor wire, and the sensor itself if it needs replacing IOG-2037D, p. 45.
A refrigerant leak, if the sensor reports one as EAL. The table’s action for EAL is to investigate the indoor coil for a refrigerant leak; the furnace resumes normal operation once a leak is no longer detected and the 5-minute delay period is over IOG-2037D, p. 45.

Notes for different models

Board or series	Code	Meaning in the table	Source
GR9, GD9, VR9, GRVT, GRVM, RVS lines; GMVC96BB (revision printed November 2026)	EAF	“Furnace has lost communication with the R-32 sensor and the furnace is in mitigation mode.”	IOG-2037D, p. 45; RS6612023R2, p. 44
Alarm code tables of the GRVT96, GRVT80 and GRVM97 service manuals	EAF	“A2L Sensor Comm Alarm”	RS6612305, p. 39; RS6621305, p. 42; RS6612306, p. 40
GR9, GD9 and VR9 lines	EAL	“R-32 sensor has detected a refrigerant leak and furnace is in mitigation mode.”	IOG-2037D, p. 45
GR9, GD9 and VR9 lines	EAS	“R-32 sensor has detected a fault and furnace is in mitigation mode.”	IOG-2037D, p. 45
2026 tables	EAr	“The furnace control board has detected an issue with the internal A2L relay and is running mitigation mode.”	IOG-2037D, p. 45
2023 to 2025 tables	Ear	“A2L relay in the furnace control board has detected a fault and the furnace is in mitigation mode.”	IOG-2037A, p. 43; RS6612301, p. 37

The variable speed RVS96 instructions and the GMVC96BB service manual (printed November 2026) list the leak, sensor fault and relay codes as EA0, EA1 and EA2, next to EAF IOG-2042A, p. 48; RS6612023R2, p. 44.

Editions differ for EAF itself. The May 2024 GR9S96 service manual puts “Furnace may not be paired with an R-32 cooling unit” among the corrective actions and says to replace the R-32 sensor without “if necessary” RS6612301, p. 37. The 10/2026 installation instructions list the pairing as a possible cause and replace the sensor “if necessary” IOG-2037D, p. 45.

There is no code EA5 in the Goodman documents reviewed for this page. The code with the letter S is EAS, “R-32 sensor has detected a fault and furnace is in mitigation mode.” IOG-2037D, p. 45.