HVACopediaNTI · Boiler
Hold 31 Internal fault: SLO electronics unknown error
What the control is telling you
Control board self-check reported an internal problem: SLO electronics unknown error.
Applies to: Trinity Tft60, Tft85, Tft110, Tft154, Tft201, Tft285, Tft340, Tft399
Models that show this code
13 models in Trinity Tft
Other codes on the same units
- Hold 3 Internal fault: Hardware fault
- Hold 30 Internal fault: Flame bias shorted to adjacent pin
- Hold 30 Internal fault: Flame bias shorted to adjacent pin
- Hold 31 Internal fault: SLO electronics unknown error
- Hold 4 Internal fault: Safety Relay key feedback error
- Hold 4 Internal fault: Safety Relay key feedback error
- Hold 47 Flame rod to ground leakage
- Hold 47 Flame rod to ground leakage
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Source: NTI Trinity Tft399 Installation and Operation Manual (2018-09-07), Sec. 16.0 Troubleshooting, Table 16-3. Summarized in our own words; check the original manual for your model.
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