Noritz NR98 & NR111 Code F76
Multi-system communication error. Two or more of these heaters are installed as a quick-connect multi-system and have lost communication. Noritz's check is the quick-connect cord connection. This is the one code where an F prefix does not mean the secondary unit — Noritz excludes 76 from that rule explicitly. Multi-system on this range reaches into commercial territory: the NC380-SV-ASME and N-1321M-ASME also carry code 56 for the CCP valve that gangs them together, which the residential models in this list do not have.
Also displayed as: 76
Part replacementThe verdict
Replace a part
Nothing is wrong with either heater's ability to make hot water; they have lost the link that coordinates them, which shows up as a shortfall in capacity rather than a breakdown. The named cause is a single cable.
Typical cost: $0–$400
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 NR98 & NR111 — not averaged across the brand.
Source: Noritz Service Manual — NR50 / NR66 / NR71 / NR98 / NCC199 / NRC111 / NR111 / NC380 (Rev. July 2011) (p. 56), read Sep 2026 — the manufacturer's own documentation for this exact series.
What you can safely check
- Check the quick-connect cord between the units is seated at both ends and undamaged.
- Cycle the power on both units.
- If it stays, book a service call.
Code F76 on other Noritz series
Other Noritz series report code F76 under the same fault name, but each manual is transcribed separately and they do not read alike:
Don't confuse this with
One other Noritz NR98 & NR111 code points at a link between two boards too. They are the same symptom reported from a different place in the unit, so which one the display shows is what tells you where to look: