Noritz EZ Series & NCC199CDV Code 76
Multi-system communication error. Two or more of these heaters are installed as a Quick Connect multi-system and have lost communication with each other. Noritz's check is the Quick Connect cord connection, and the remark narrows it further: 76 is displayed only when a common duct is set. This is the one code in the table where an "F" prefix does not mean the secondary unit — Noritz excludes 76 from that rule explicitly.
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. The named cause is a single cable, which makes this one of the cheaper faults to find.
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 EZ Series & NCC199CDV — not averaged across the brand.
Source: Noritz Service Manual — NRC663 FSV, EZ98DV, EZ111DV, NCC199CDV (Rev. Oct 2017) (p. 32), 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 — the setting for common duct operation is part of the diagnosis.
Frequently asked questions
I only have one water heater. Can I get a code 76?
You should not. Noritz displays 76 only when the common duct setting is active, which is a multi-system configuration. On a single unit it points at a setting that does not match the installation, which is worth having corrected.
Code 76 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: