NTI · Boiler troubleshooting
Circulator (CH or DHW) not running
What is going on
Pump output not powering the circulator.
Likely causes
- Blown fuse B (PUMP A and C) or fuse A (PUMP B)
- Control output dead
- Circulator failed
Check in this order
- Check fuse B (and fuse A for the boiler pump)
- On the pump diagnostic page, switch the pump on manually and check for 120 VAC at the pump terminals on the line voltage strip
- If no 120 VAC, replace the control; if voltage is present and the pump will not turn, replace the pump
Applies to: Trinity Tft60, Tft85, Tft110, Tft154, Tft201, Tft285, Tft340, Tft399
More boiler guides
Related
Take it to the job
All guides, error codes and tips work offline in the HVACopedia app.
Source: NTI Trinity Tft399 Installation and Operation Manual (2018-09-07), Sec. 16.0 Troubleshooting. Written in our own words; check the manual for your exact model.
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.