Noritz error code 29: condensate drain problem

Condensing Noritz heaters produce acidic condensate that must drain away. When it cannot, the unit shows code 29 and stops to keep water from backing up.

Code 29 only applies to condensing models.

What to check

1. Follow the condensate line from the heater to the drain and look for kinks, sags, debris or ice.
2. Check the neutralizer, if installed, for clogging. Noritz uses separate warning codes as the neutralizer nears the end of its life.
3. Make sure the drain line has a proper air gap where it enters the drain.
4. Reset the unit once the line drains freely.

When to call a contractor

Call a licensed contractor or Noritz service technician if code 29 returns after the condensate line and neutralizer drain freely, or if you cannot safely reach or check the drain line. At that point the blockage is likely inside the heater, such as in its internal condensate trap, and that part should be serviced by a professional.