NTI Boiler: Condensate drain setup

Condensate drain setup on a NTI boiler: A condensing boiler like this one wrings the heat out of the flue gas, and what drips out is acidic condensate. That water has to go somewhere safe, in the right kind of pipe, or you will chew through fittings and flood a floor. It is not hard, but a few details matter: material, slope, and keeping the line from freezing. Get these right at install and the boiler will not give you a nuisance call later.

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

Applies to: TRX150 and related TRX models

Common causes of condensate drain setup

• Wrong pipe material such as steel, copper or brass used for condensate
• Condensate line without enough slope, leaving water trapped
• Outlet lower than the drain with no condensate pump
• Long horizontal run that vacuum locks without a vent
• Line routed through a cold space where it freezes

How to fix condensate drain setup: step by step

1. Use only PVC or CPVC pipe for condensate. Never use steel, copper or brass, because the acid eats them.
2. Connect the supplied hose to the barbed outlet and run it to a suitable indoor drain.
3. Slope the line downward away from the boiler and support it so the outlet fitting is not strained.
4. If the outlet is lower than the drain, install a condensate pump and wire its alarm leads to a warning device.
5. Add a vent in long horizontal runs so a vacuum lock does not hold water back.
6. Keep the condensate line away from freezing temperatures.
7. Pour some water through the line at startup and watch that it drains freely and does not back up.

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

Models

TRX085TRX110CTRX150TRX199TRX199C