HVACopediaNTI · Boiler
Alert 351 Abnormal Recycle: Invalid zero crossing
What the control is telling you
Abnormal Recycle: Invalid zero crossing.
Applies to: Trinity Tft60, Tft85, Tft110, Tft155, Tft175, Tft200, Tft250, Tft300, Tft399
Models that show this code
13 models in Trinity Tft
Other codes on the same units
- Alert 349 Abnormal Recycle: Hardware HFS LCI shorted
- Alert 35 Range PCB was configured
- Alert 35 Range PCB was configured
- Alert 350 Abnormal Recycle: Hardware HFS LFS shorted
- Alert 352 Abnormal Recycle: fault stack sensor
- Alert 353 Abnormal Recycle: stack limit
- Alert 354 Abnormal Recycle: delta T limit
- Alert 355 Abnormal Recycle: fault outlet sensor
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Source: NTI Tft60-399 Installation and Operation Instructions (rev. 2012-04-09), Sec. 15.0 Troubleshooting, Table 15-4. 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.