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
The same code number can mean something different on another series — make sure you're reading the page for your exact unit: