Gas valve fault – control senses 24V present at gas valve when it should not be, or control tried to turn on gas valve but 24V not sensed.
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M+ Max·Trane Furnace
ERR 93 on my Trane Furnace
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Gas valve fault – control senses 24V present at
From Service Manual 660101, p.33:
1.Access service mode to confirm the active fault code and read stored error history.
2.Measure control board supply voltage at the test points. Expected: 12 VDC and 5 VDC; a drop below 4.75 VDC on the logic rail points to a failed onboard regulator.
3.Inspect all connectors on the main control for corrosion, thermal stress, or backed-out pins. Reseat each connector with the power disconnected.
Part WPW10804018
Electronic control board
Related Trane furnace codes
All Trane furnace codes →- 1Flame sensed when no flame should be present.
- 1 Flash (Red)Normal LitePort data transmission
- 1 GREENStandby mode or call for cooling.
- 1 GREEN / 1 AMBER1st stage call for heat.
- 1 REDFlame sensed when no flame should be present.
- 10Gas valve energized without call for heat.
- 10 FlashCommunication fault
- 10 REDGas valve energized without call for heat.
View all 78 Trane furnace codes
- 11Primary limit has been open for more than 5 minutes, check…
- 12Ignitor relay failure internal in board
- 12 REDIgnitor relay failure internal in board
- 2Pressure switch is stuck closed.
- 2 FlashFlame lost or ignition failure
- 2 GREEN / 1 AMBER2nd stage call for heat.
- 2 REDPressure switch stuck closed.
- 31st stage pressure switch is stuck open (not closing).
- 3 Double2nd stage pressure switch open
- 3 DOUBLE RED2nd stage pressure switch open; system reverts back to 1st…
- 3 FlashPressure switch or inducer error
- 3 GREEN / 1 AMBERW2 call present without W1.
- 3 RED1st stage pressure switch is open or not closing.
- 4Open primary limit, flame roll out or reverse flow switch.
- 4 FlashHigh temperature limit fault
- 4 GREEN / 1 AMBERY call present without G.
- 4 REDOpen thermal limit or open rollout.
- 5Open roll out switch or open low voltage fuse.
- 5 FlashFlame detect fault
- 5 REDOpen low voltage fuse.
- 61st stage pressure switch has opened 5 times within one…
- 6 FlashLine polarity fault (voltage reverse polarity), ground…
- 6 RED1st stage pressure switch opened 5 times within one cycle
- 7System lockout Retry
- 7 FlashExternal gas valve circuit error
- 7 REDSystem lockout Retry.
- 8System lockout Recycle
- 8 FlashLow flame sense signal
- 8 REDSystem lockout Recycle.
- 9Reverse polarity or poor grounding.
- 9 FlashOpen inducer limit error
- 9 REDReverse polarity or poor grounding.
- CFMB Blinking Red LEDFasco Motor Control Board (CFMB) has shut down due to…
- ERR 10Ignition means fault
- ERR 101Y1 relay failure
- ERR 114Bad or missing personality module
- ERR 119Temperature sensor failure
- ERR 139Communication failure
- ERR 18Internal control failure.
- ERR 22Soft lockout due to flame lost or ignition retries (10…
- ERR 26High temp limit fault
- ERR 34Line polarity fault
- ERR 87Flame detect fault
- ERR 91Communication fault
- Fast FlashPersonality Module error
- Green Continuous / Red FlashingGas valve miswired or flame signal present at a call for…
- Green Fast FlashNormal operation, call for heat present.
- Green OFF / Red ContinuousInternal fault detected on Texas Instruments ignition…
- Green OFF / Red FlashingIgnition control module locked out on failure to establish…
- Green OFF / Red Flashing (during ignition try)No flame signal on try for ignition or flame signal lost…
- Green Slow FlashNormal operation, no call for heat.
- Green/Red LEDs on continuouslyFuse open or internal control failure.
- None (AC VOLTS HI)AC line voltage too high.
- None (AC VOLTS LOW)AC line voltage too low.
- None (CAP MISMATCH)Compressor size does not match capacity in Personality…
- None (CHECK FUSE)24V control fuse is open.
- None (ID MTR ERR)Blower HP/OEM does not match Personality Module data.
- None (TS 1 OPEN)Temperature sensor 1 is open.
- None (TS 1 SHORT)Temperature sensor 1 is shorted.
- None (TS 2 OPEN)Temperature sensor 2 is open.
- None (TS 2 SHORT)Temperature sensor 2 is shorted.
- None (TWIN ERROR)Twinning not allowed with variable speed
- None (Y1 OFF ERR)Y1 relay failure
- None (Y1 ON ERR)Y1 output is ON when it should be OFF.
- RapidTwinning Error, incorrect 24V Phasing.
- RAPID GREEN / 1 AMBERLow flame sense current.
- Solid ONInternal control failure (ERR 18)
- Solid RedInternal gas valve circuit error (damaged furnace control)
- Solid Red (continuous reset)Continuous reset caused by an internal error (damaged…
- Solid STATUS (Red OFF)24VAC fuse open
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