HVACopediaNTI · Boiler
Lockout 59 Internal fault: Mux pin shorted
What the control is telling you
Control board self-check reported an internal problem: Mux pin shorted.
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
- Lockout 55 Application configuration data block CRC errors
- Lockout 58 Internal fault: HFS shorted to IAS
- Lockout 58 Internal fault: HFS shorted to IAS
- Lockout 59 Internal fault: Mux pin shorted
- Lockout 60 Internal fault: HFS shorted to LFS
- Lockout 60 Internal fault: HFS shorted to LFS
- Lockout 71 Input power frequency mismatch
- Lockout 82 Stack limit
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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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