HVACopediaNTI · Boiler
Alert 233 Lead-lag outdoor temperature invalid
What the control is telling you
No usable outdoor sensor reading for lead-lag.
Applies to: Trinity Tft60, Tft85, Tft110, Tft154, Tft201, Tft285, Tft340, Tft399
Likely causes
- Same as Alert 248
Test and repair steps
- Follow the Alert 248 checks
Models that show this code
13 models in Trinity Tft
Other codes on the same units
- Alert 23 Backup Alert PCB was restored from active one
- Alert 231 LL set point was invalid
- Alert 232 LL time of day set point was invalid
- Alert 233 Lead-lag outdoor temperature invalid
- Alert 234 LL ODR time of day set point was invalid
- Alert 235 LL ODR time of day set point exceeded normal set point
- Alert 236 LL max outdoor set point was invalid
- Alert 237 LL min outdoor set point was invalid
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Source: NTI Trinity Tft399 Installation and Operation Manual (2018-09-07), Sec. 16.0 Troubleshooting, Table 16-4. Summarized in our own words; check the original manual for your model.
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