Trane rooftop ignition boards report faults as LED flash counts. On a Precedent unit, 2 flashes means failure to sense flame, 3 a pressure switch fault, 4 an open TCO, 5 flame sensed with the valve not energized, and 6 an open flame rollout switch. Voyager II ReliaTel units use a different list.
Two board types, two lists
Trane publishes the ignition LED codes for its light commercial rooftop units in three support articles. They do not describe a single table. They describe two kinds of ignition board, and the flash patterns are not identical between them.
- Electromechanical ignition board. Trane lists 2 flashes as a 1 hour lockout, 3 flashes as the pressure switch, 4 as the TCO open, 5 as flame without gas, 6 as the rollout switch open, and 7 as W1 and W2 swapped.
- ReliaTel ignition module (IGN). Trane lists a green LED on as normal, a slow flash as an active call, and a fast flash as not communicating with the RTRM. Fault flashes are 2 for lockout (no flame), 3 for the pressure switch, 4 for the TCO open, 5 for flame sensed without the gas valve, and 6 for flame rollout open.
The first practical step is to identify which board you have. The 7 flash (W1 and W2 swapped) appears only on the electromechanical list, and the fast flash (not communicating with the RTRM) appears only on the ReliaTel list. If you see one of those two patterns, that tells you which table to use. Where the pattern is shared, such as 2, 3, 4, 5 or 6, the board type still matters because the meaning of the code is worded differently in each of Trane’s articles. This article keeps them separate for that reason.
Precedent gas heat codes
Trane’s article on Precedent gas heat fault codes lists the following:
- Off: no power, or board failure.
- 2 flashes: failure to sense flame.
- 3 flashes: the pressure switch failed to open when the CBM stops, or failed to close when the CBM starts.
- 4 flashes: TCO-1 or TCO-2 open.
- 5 flashes: flame sensed while the valve is not energized. Trane points to a stuck valve or the control board.
- 6 flashes: flame rollout switch open. Trane points to an airflow restriction or heat exchanger damage.
- 7 flashes: W2 before W1. This applies to the electromechanical board only, and it is a wiring problem.
“CBM” and “TCO” are Trane’s abbreviations, used here exactly as the article uses them.
Voyager II (ReliaTel) gas heat codes
Trane’s article on ReliaTel controlled Voyager II units lists a shorter set:
- 2 flashes: failure to ignite. Trane lists no spark and low gas pressure among the possibilities.
- 4 flashes: TCO open, which Trane associates with excess heat in the combustion chamber and low airflow.
- 5 flashes: stuck gas valve.
- Fast flash: the ignition board is not communicating with the RTRM. Trane points to wiring, the ignition module or the RTRM.
The Voyager II article does not list 3 or 6 flashes in the material we worked from. The ReliaTel IGN list in Trane’s LED codes article does include them (3 for the pressure switch, 6 for flame rollout open). If your Voyager II shows 3 or 6, use the LED codes article and your unit’s service literature.
How to work from a flash code
- Identify the board and the unit. Note whether it is electromechanical or a ReliaTel IGN module, and whether the unit is a Precedent or a Voyager II. Use the table for your board only.
- Count the flashes more than once. Watch several cycles so you do not mistake a pause for the end of a count. Record the pattern before you change anything.
- Isolate before you work on the heat section. This is a gas-fired section with line-voltage and control wiring. Follow your site’s lockout/tagout and gas shutoff procedure.
- Match the pattern to the correct list. Write the matching description next to the code so you work from Trane’s wording rather than from memory.
- For a pressure switch code (3), check the switch and its circuit. Trane describes the fault as the switch failing to open or close in step with the CBM stopping and starting, and its articles word that sequence differently, so confirm it against your unit’s service literature.
- For an open TCO or rollout code (4 or 6), look for the conditions Trane names: low airflow, excess combustion-chamber heat, or heat exchanger damage. Do not jumper a limit or rollout switch to get the unit running.
- For flame sensed with the valve not energized (5), Trane points to a stuck valve or the control board. Treat it as a safety condition and shut off the gas before you investigate.
- For a fast flash, check the wiring between the ignition board and the RTRM, the ignition module and the RTRM, the three possibilities Trane’s article lists. Start with the wiring.
- For a 7 flash on an electromechanical board, check the W1 and W2 wiring.
- Order only after you have the part numbers. Take them from the failed part or your unit’s parts documentation.
Parts involved
Items we list under the Trane name for gas-heat work are shown below. Several carry the “— Replacement” label in their titles, and we describe each by its title only. We do not claim fit to a specific Trane unit; confirm by the number on your part and your nameplate.
| Component | Role in this issue | Where to find it |
|---|---|---|
| Pressure switch | Code 3 concerns the pressure switch. Trane’s articles do not name a part number for it. This listing is titled a pressure switch with bracket. | Trane CNT03520 Pressure Switch with Bracket — Replacement |
| Vacuum switch | Listed as a vacuum switch, not a pressure switch. Match it by the number on your existing switch, since the title does not say it corresponds to a particular code. | Trane C341750P01 Vacuum Switch With Bracket Swt2293 — Replacement |
| Draft inducer | On the combustion-air side of gas heat. Trane’s code articles do not name an inducer as the cause of any listed code. | Trane BLW01310 Draft Inducer 230V, 60HZ, 3480 Rpm W/gasket — Replacement |
| Draft inducer | Listed at a different voltage and speed than the item above. Same note: match by number and nameplate. | Trane D330757P01 Draft Inducer 115V/60HZ 3000 Rpm — Replacement |
| Ignition board, flame rollout switch, TCO, gas valve | Named in Trane’s code descriptions. We have not matched these to listings, so send the number from the part. | Request a quote |
| More switches | Other pressure and vacuum switches, listed under several brands. | NBK Switches |
Scope: This article covers the Trane light commercial rooftop ignition LED codes as listed in the three Trane support articles under Sources: electromechanical and ReliaTel IGN boards, Precedent gas heat, and ReliaTel controlled Voyager II. Other Trane equipment, other brands’ rooftop units and residential furnace code tables are not covered. Do not apply a furnace code chart to a rooftop unit. Check your unit’s own service literature.
Before you order
Confirm your unit’s exact model and serial number from its nameplate before ordering. Search the part number in our site search, or browse the Trane replacement parts collection. If the number you need is not listed, use our request a quote page, or contact us at help@totalhvacparts.com and we will help confirm fit. For the difference between OEM and replacement-labeled parts, see our OEM vs. aftermarket guide.
If the code points to the RTRM rather than the ignition board, our article on the RTRM 2-flash code and J6 fail codes covers that side.
Frequently Asked Questions
What does a 5 flash mean on a Trane ignition board?
On a Precedent unit, Trane lists 5 flashes as flame sensed while the valve is not energized, pointing to a stuck valve or the control board. On a ReliaTel Voyager II, Trane lists 5 flashes as a stuck gas valve. Shut off the gas before investigating.
What does a fast flash mean on a Trane ReliaTel ignition board?
Trane lists a fast flash as the ignition board not communicating with the RTRM. For Voyager II units, Trane points to wiring, the ignition module or the RTRM. Check the wiring first.
What does 2 flash mean on a Trane Voyager II?
Trane lists 2 flashes on a ReliaTel controlled Voyager II as failure to ignite, with no spark and low gas pressure among the possible reasons. On a Precedent, Trane words it as failure to sense flame.
What does a 7 flash mean on a Trane ignition board?
Trane lists 7 flashes as W2 before W1, and says it applies to the electromechanical board only. It is a wiring problem. Check the W1 and W2 wiring first.
What does 6 flash mean on a Trane rooftop unit?
Six flashes is flame rollout switch open. Trane points to an airflow restriction or heat exchanger damage on Precedent units. Find the cause before you reset or replace anything.
Sources
- Trane support, “List of Light Commercial LED Codes” (electromechanical and ReliaTel IGN ignition LED patterns)
- Trane support, “What are the gas heat fault codes for Precedent units?” (Precedent gas heat codes)
- Trane support, “What are the gas heat fault codes for Reliatel controlled Voyager II units?” (Voyager II ReliaTel codes)
This equipment involves natural gas or propane combustion, line-voltage electrical components and rotating equipment. Service should be performed only by qualified personnel, following Trane’s service literature for your unit, applicable fuel-gas codes and your facility’s lockout/tagout procedures.