HVACopediaRinnai · Wall furnace
16 Room overheat (above 104°F / 40°C)
What the control is telling you
The room temperature went above 104°F (40°C), so the furnace stopped heating.
Applies to: Rinnai EnergySaver direct vent wall furnaces EX08DT, EX11DT, EX17DT, EX22DT
Likely causes
- Room temperature above 104°F (40°C)
Test and repair steps
- Lower the room temperature (ventilate the room or lower the set temperature).
- Turn the furnace off and back on with the ON/OFF button to try to clear the code.
- If the code stays or comes back on the next operation, a trained and qualified technician must service the unit.
Settings for these units
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Source: Rinnai EX08DT/EX11DT and EX17DT/EX22DT Installation and Operation Manuals (200000083, 200000084), Table 9 'Diagnostic Codes', p.35–36. Summarized in our own words; check the original manual for your model.
Homeowner looking at this code? See what it means for you and when to call a technician.
For licensed technicians. Gas, electrical and refrigerant work must be done by a qualified, licensed person. Shut off power and gas before servicing, never bypass a safety control, and follow the manufacturer’s manual for the exact model; it and local codes always take priority. HVACopedia is not affiliated with any manufacturer; brand and model names only identify the equipment.