Error codes

The meaning of each code as the manufacturer's manual words it, the page it is on, and the checks the manual leaves to the owner.

Tankless water heaters

• Navien37 codesNPE-A2, NPE-S2, NPN. Step-by-step checks for 8 of them.
• Rheem116 codesRTGH-3, RTG-3, RTG-R-3, IKONIC, ThermaForce, Ruud Mid-Efficiency. Step-by-step checks for 8 of them.
• Rinnai38 codesRU/RUR/RSC, RX, RE/REP, V, RL/VC. Step-by-step checks for 10 of them.

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