Rinnai 16 Error Code: High outgoing temperature
Updated October 2026 · Sourced from Rinnai documentation
🛑 Turn it off and call a licensed pro
A safety shutdown because the water heater is too hot. The manual says to confirm the fan motor works and to replace the gas valve assembly if needed.
Is it safe to keep running? No. Turn it off and get it checked. This is a safety shutdown. Call a qualified professional if it returns.
16 at a glance
| Code / how it shows | Meaning | Applies to |
|---|---|---|
| 16 Code shown on the temperature controller display | High outgoing temperature | SENSEI N Series residential condensing: RU199i, RU180i, RU160i, RU130i (indoor) and RU199e, RU180e, RU160e, RU130e (outdoor) |
Check this first
Only steps a homeowner can do safely. Do not open electrical panels or the burner area.
- Turn off hot water use and let the unit cool.
- Turn power off, wait, then back on.
🛑 Stop and call a licensed pro if
- This is a safety shutdown. Call a qualified professional if it returns.
- You smell gas. Leave the house, do not touch switches, and call your gas utility from outside.
- Codes for flame failure, overheating, venting or the control board that return after one reset.
- Water leaking from the heater, the relief valve discharging, or scorching around the burner area.
- A carbon monoxide alarm sounds. Get everyone outside and call 911 or the fire department.
Safe first steps for any Rinnai code
- Write down the exact code shown on the controller or the number of status light flashes.
- Turn the water heater power off and back on (or press the reset button the manual describes) once. If the code comes back, stop resetting.
- Make sure the gas supply valve to the heater is open and other gas appliances in the home are working.
- Make sure the cold water supply valve is fully open and hot water taps are not partly closed.
- Look at the outside vent terminal for snow, ice, leaves or anything blocking it (look only).
Source: Rinnai SENSEI N Series Residential Installation and Operation Manual (100000467), 5.6 Diagnostic Codes, p.74. Codes are series-specific, so your unit's own manual is the final word. Reviewed October 2026.
Ryan Giles · Red Seal Certified Plumber · Ask a plumber · Ask an HVAC technician
Related Rinnai codes
03 : Power interruption during bath fill05 : By-pass flow control10 : Air supply or exhaust blockage, or condensate trap full11 : No ignition12 : No flame14 : Heat exchanger overheat15 : Venturi control17 : Venturi blockage19 : Electrical grounding21 : Data transfer error25 : Condensate pump (accessory)32 : Outgoing thermistor