NTI Boiler: Connect 120 V power for CH and DHW circulators

Connect 120 V power for CH and DHW circulators on a NTI boiler: Field wiring for the central heating and domestic hot water pumps at the boiler junction box. The 120 V circulator cables land on CN5 for the CH pump and CN4 for the DHW pump. It is simple work, but it is line voltage and gas is on the unit.

Homeowner with a boiler problem? Call (647) 657-2977 or book a service call — licensed technicians across Vaughan and the GTA.

Applies to: TRX150

Common causes of connect 120 v power for ch and dhw circulators

• New install where external circulators are being added
• Replacing a circulator or its cable
• Rewiring after a cable was damaged
• Switching to external pumps from internal ones

How to fix connect 120 v power for ch and dhw circulators: step by step

1. Shut off power at the boiler and at the circuit breaker, then verify it is dead with a meter.
2. Shut off gas at the manual shutoff.
3. Remove the boiler front cover.
4. Disconnect the three clips and open the junction box.
5. Feed the circulator power cable through the side panel hole and secure it with a strain relief or conduit hub.
6. Connect the cable to CN5 for the CH pump and CN4 for the DHW pump.
7. Check that the new cable sits correctly inside the control panel.
8. Reconnect the junction box cover and reinstall the front cover.
9. Restore gas to the boiler.
10. Restore power to the boiler and run both pumps to confirm.

If the unit shows an error code, look it up: NTI Boiler codes

Models

TRX085TRX110CTRX150TRX199TRX199C