Rinnai Error Code 371: Indirect tank thermistor fault (Boiler)
Rinnai error code 371 on a boiler means: Indirect tank thermistor fault. It is also called Rinnai diagnostic code 371.
Homeowner? What Rinnai code 371 means for you
Check, then call Your boiler is reporting: Indirect tank thermistor fault. This is often caused by something simple. Try the safe checks below; if the code returns, book a service call before it turns into a no-heat or no-hot-water emergency.
Safe things you can check yourself
- Check the thermostat: right mode (Heat or Cool), set a few degrees past room temperature, and fresh batteries if it uses them.
- Make sure the unit has power: its on/off switch (often looks like a light switch near the unit) is ON and the breaker in the electrical panel is not tripped.
- Look at the pressure gauge on the boiler. If it reads much lower than usual or near zero, or water is leaking, call a technician.
- Outside, make sure the intake and exhaust pipes or vent cap are not blocked by snow, ice, leaves or a nest.
- Check that the boiler gas valve is open (handle in line with the pipe).
- Try one reset: turn the power off for 30 seconds, then back on. If the code comes back, stop resetting and call a technician.
Call (647) 657-2977Book a service call
Licensed technicians serving Vaughan, Toronto and the GTA.
What does Rinnai error code 371 mean?
Fault in the indirect DHW tank thermistor used when the boiler controls an indirect tank by thermistor.
Applies to: I-Series Plus boilers — 150K BTU and smaller and 175K BTU and higher (Solo)
Common causes of Rinnai code 371
- Parameter 28 or 29 set incorrectly
- Thermistor unplugged (reads -40)
- Loose, broken or damaged thermistor wiring
A technician checks these and 1 other possible causes on site before replacing any part.
Rinnai models that use code 371
IP060SIP090SIP120SIP150SIP175SIP199S
Other Rinnai Boiler codes
All Rinnai Boiler error codes →
Rinnai code 371: homeowner questions
What does Rinnai code 371 mean?
Indirect tank thermistor fault. Fault in the indirect DHW tank thermistor used when the boiler controls an indirect tank by thermistor.
Is it safe to keep using my boiler with code 371?
It depends on the cause. This is often caused by something simple. Try the safe checks below; if the code returns, book a service call before it turns into a no-heat or no-hot-water emergency.
Can I reset Rinnai code 371 myself?
You can try one reset (power off for 30 seconds, then on). If Rinnai code 371 comes back, the cause is still there and a licensed technician should check it.
Who can fix Rinnai code 371 near me?
Aurora Star Tech Inc. repairs Rinnai boilers in Vaughan, Toronto and across the GTA. Call (647) 657-2977 or book a service call online.
Homeowner help: Boiler Not Heating: What to Check
Troubleshooting guides
- No heat or some zones cold All brands · Boiler
Source: Rinnai Troubleshooting I-Series Plus Boiler Diagnostic Codes (800000375), p.23–24. Written in our own words as a summary; always check the original manual.
General guidance for qualified technicians. The manufacturer's installation and service manual and local codes always take priority. Aurora Star Tech is not affiliated with, endorsed by or sponsored by any equipment manufacturer; brand and model names are used only to identify equipment and belong to their owners.