NTI · Boiler
5 P2 2nd ignition failed
What the control is telling you
Second ignition attempt was unsuccessful. Warning.
Applies to: TRX150
Likely causes
- Gas pressure out of range
- Faulty gas valve wiring
- Faulty flame sensor
- Faulty igniter transformer or igniter
- Unstable flame
Test and repair steps
- Monitor gas pressure during operation. Natural gas should be 3.5 to 10.5 in. WC. For LP, 8 to 13 in. WC.
- Check the gas valve wire and make sure the connection is secure.
- Check the flame detection sensor and its connections. Signal should be more than 2.5 DC before ignition and less than 2.5 DC after ignition.
- Check the igniter transformer connection.
- Clean the spark igniter with steel wool. Check the gap (2/16 to 3/16 in.).
- Replace the spark igniter if damaged.
- Make sure the flame is stable when lit.
- If the problem continues, replace the main control.
Models that show this code
5 models in TRX
Other codes on the same units
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Source: NTI TRX150 manual, p. 86. Summarized in our own words; check the original manual for your model.
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For licensed technicians. Gas, electrical and refrigerant work must be done by a qualified, licensed person. Shut off power and gas before servicing, never bypass a safety control, and follow the manufacturer’s manual for the exact model; it and local codes always take priority. HVACopedia is not affiliated with any manufacturer; brand and model names only identify the equipment.