Trane Error Code E2.3: 1st stage gas valve not powered when it should be (10 times) (Furnace)

Updated October 13, 2026 · by Aurora Star Tech Inc.

Trane error code E2.3 on a furnace means: 1st stage gas valve not powered when it should be (10 times). It is also called Trane diagnostic code E2.3.

High severityFurnaceTrane S8V2 · Trane S8B1 · Trane S8X1 · Trane S8X2

Homeowner? What Trane code E2.3 means for you

Call a technician Your furnace is reporting: 1st stage gas valve not powered when it should be (10 times). The furnace has locked out or cannot run properly. One reset is fine; if the code comes back, it needs a licensed technician to find the cause.

Safe things you can check yourself

Check the thermostat: right mode (Heat or Cool), set a few degrees past room temperature, and fresh batteries if it uses them.
Make sure the unit has power: its on/off switch (often looks like a light switch near the unit) is ON and the breaker in the electrical panel is not tripped.
Make sure the furnace front door or panel is closed properly; many furnaces will not run with the door switch open.
Look at the air filter. If it is grey and clogged, replace it; a blocked filter causes many shutdowns.
Outside, make sure the intake and exhaust pipes or vent cap are not blocked by snow, ice, leaves or a nest.
Check that the gas valve next to the furnace is open (handle in line with the pipe). Do not force it.
Try one reset: turn the power off for 30 seconds, then back on. If the code comes back, stop resetting and call a technician.

Call (647) 657-2977 Book a service call

Licensed technicians serving Vaughan, Toronto and the GTA.

What does Trane error code E2.3 mean?

The control did not see 24 VAC on the MVL (1st stage valve) output when it expected it, 10 times in one heat call, and locks out for an hour. The S8V2 flowchart index words this as valve energized when it should not be; the code table and diagram say not energized.

Applies to: Trane S8V2 (80%, 2-stage, variable speed, Link) and S8B1 / S8X1 / S8X2 (80%, 1- and 2-stage)

Common causes of Trane code E2.3

Interrupted 24 V circuit (blower door switch, unplugged harness)
Power interruption or wind gust during the cycle
IFC gas valve relay fault

Safety: Gas, electrical and refrigerant work must be done by a licensed technician. Turn off power and gas before servicing, never bypass a safety control, and always follow the manufacturer's manual for your exact model.

Trane models that use code E2.3

Show all 37 models

S8B1A026M2PSAB S8B1A040M3PSAB S8B1B040M2PSAB S8B1B060M3PSAB S8B1B060M4PSAB S8B1B080M4PSAB S8B1C080M5PSAB S8B1C100M5PSAB S8B1D120M5PSAB S8V2A040M3PCB S8V2A040M3PD S8V2B060M4PCB S8V2B060M4PD S8V2B080M4PCB S8V2B080M4PD S8V2C080M5PCB S8V2C080M5PD S8V2C100M5PCB S8V2C100M5PD S8V2D120M5PCB S8V2D120M5PD S8X1A026M2PSAB S8X1A040M3PSAB S8X1B040M2PSAB S8X1B060M3PSAB S8X1B060M4PSAB S8X1B080M4PSAB S8X1C080M5PSAB S8X1C100M5PSAB S8X1D120M5PSAB S8X2A040M3PSAB S8X2B060M3PSAB S8X2B060M4PSAB S8X2B080M4PSAB S8X2C080M5PSAB S8X2C100M5PSAB S8X2D120M5PSAB

Other Trane Furnace codes

Code	Meaning
E01	Furnace control internal failure
E04	Open limit (main limit, rollout or reverse airflow)
E05	Flame sensed when no flame should be present
E08	Low flame signal (still running)
E2.1	Ignition retries exceeded - flame never proven (1 hour lockout)
E2.2	Flame recycles exceeded - flame lost after lighting (1 hour lockout)
E3.1	1st stage pressure switch (PS1) closed when it should be open
E3.2	1st stage pressure switch (PS1) open when it should be closed
E3.3	2nd stage pressure switch (PS2) closed when it should be open
E3.4	2nd stage pressure switch (PS2) open when it should be closed
E4.0	Main high limit open
E4.1	Reverse airflow limit open

All Trane Furnace error codes →

Trane code E2.3: homeowner questions

What does Trane code E2.3 mean?

1st stage gas valve not powered when it should be (10 times). The control did not see 24 VAC on the MVL (1st stage valve) output when it expected it, 10 times in one heat call, and locks out for an hour. The S8V2 flowchart index words this as valve energized when it should not be; the code table and…

Is it safe to keep using my furnace with code E2.3?

It depends on the cause. The furnace has locked out or cannot run properly. One reset is fine; if the code comes back, it needs a licensed technician to find the cause.

Can I reset Trane code E2.3 myself?

You can try one reset (power off for 30 seconds, then on). If Trane code E2.3 comes back, the cause is still there and a licensed technician should check it.

Who can fix Trane code E2.3 near me?

Aurora Star Tech Inc. repairs Trane furnaces in Vaughan, Toronto and across the GTA. Call (647) 657-2977 or book a service call online.

Homeowner help: Furnace Not Turning On: What to Check · Furnace Blinking Light: What the Flash Codes Mean

Troubleshooting guides

Blowing cold air All brands · Furnace
No heat All brands · Furnace
Short cycling All brands · Furnace
Reading and clearing fault history - Trane S-Series IFC Trane · Furnace

Source: Trane FNR-SVX003A-EN (S8V2 installer's guide) - section Integrated Furnace Control Display Codes, Table 37 Error codes; Trane FNR-SVX003A-EN (S8V2 installer's guide) - section Troubleshooting (flowcharts); Trane 18-CE14D1-1A-EN (S8B1/S8X1/S8X2 installer's guide) - section Integrated Furnace Control Display Codes, Error Codes. Written in our own words as a summary; always check the original manual.

General guidance for qualified technicians. The manufacturer's installation and service manual and local codes always take priority. Aurora Star Tech is not affiliated with, endorsed by or sponsored by any equipment manufacturer; brand and model names are used only to identify equipment and belong to their owners.