NTI Boiler: Access the low voltage wiring connections
Access the low voltage wiring connections on a NTI boiler: Anytime you wire a room thermostat or chase a low voltage problem on the TRX150, you have to get into the control panel first. What I usually see is people skip the shutoffs because it is only low voltage, but the main board has line voltage on it too, so power comes off first. The panel hinges forward once the screw and tabs are dealt with.
Applies to: TRX150
Common causes of access the low voltage wiring connections
- Control panel still held by the cross-member screw or the side tabs
- Power left on while working near the main board
- Factory jumper on TT1 left in place when a thermostat is wired
How to fix access the low voltage wiring connections: step by step
- Shut off power at the boiler and at the circuit breaker.
- Shut off gas at the manual shutoff.
- Remove the boiler front cover.
- Remove the screw holding the control panel to the cross-member.
- Push in the tabs and pull the control panel housing forward.
- Disconnect the two clips.
- Open the control panel cover to reach the main PCB. If you are wiring a room thermostat, remove the factory jumper from TT1.
If the unit shows an error code, look it up: NTI Boiler codes
Models
TRX085TRX110CTRX150TRX199TRX199C
Source: NTI TRX150 manual, p. 54-55. Written in our own words as a summary; always check the original manual.
General guidance for qualified technicians. The manufacturer's installation and service manual and local codes always take priority. Aurora Star Tech is not affiliated with, endorsed by or sponsored by any equipment manufacturer; brand and model names are used only to identify equipment and belong to their owners.