Noritz NCC199 & NRC111 Code 93
Neutralizer life cycle has ended. The countdown that started at code 92 has finished. Noritz's instruction is the same — refer to the instructions included with the replacement neutralizer — and the difference is that the appliance no longer considers the cartridge to be doing anything.
Also displayed as: F93
DIY fixThe verdict
Replace a part
Replace the cartridge. It is one of the genuinely homeowner-serviceable parts on a condensing heater — it sits in the condensate line below the unit, not inside the cabinet, and comes apart without touching gas or mains electricity.
Typical cost: $40–$200
US estimate for parts and labor. Prices vary by region and by who does the work — see how we estimate costs.
What the manual says
The meaning above is transcribed from the manufacturer's diagnostic documentation for the NCC199 & NRC111 — not averaged across the brand.
Source: Noritz Service Manual — NR50 / NR66 / NR71 / NR98 / NCC199 / NRC111 / NR111 / NC380 (Rev. July 2011) (p. 55), read Sep 2026 — the manufacturer's own documentation for this exact series.
What you can safely check
- Switch the unit off and close the water supply before opening the housing.
- Catch what drains out of the cartridge — it is acidic and will mark what it lands on.
- Replace the media or the cartridge, following the instructions supplied with it.
- Check the drain line downstream while it is off.
- If the code stays after a genuine replacement, book a service call — code 29 covers the electrode, and that is inside the unit.