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Rinnai Error Codes & Diagnostic Codes

Updated · by Aurora Star Tech Inc.

Rinnai error codes and diagnostic codes: look up a code to see what it means, the likely causes and the steps to fix it.

Rinnai error codes by equipment type

Rinnai Boiler error codes

CodeMeaning
100Air intake/exhaust blockage or full condensate trap
110Ignition failure
120Flame failure (flame lost during operation)
140Overheat switch tripped (heat exchanger overheating)
150Venturi control fault
170Venturi blockage / position mismatch
180Gas valve air/fuel adjustment limit reached
190Electrical grounding / short in DC circuit
210Data transfer error
220Gas valve position not detected (reed switch)
250Condensate pump switch tripped (accessory)
303Secondary system thermistor fault
310Freeze protection thermistor fault
353CH supply thermistor fault
363CH return thermistor fault
371Indirect tank thermistor fault
380Exhaust thermistor fault
393Outdoor temperature sensor fault
400Water pressure sensor communication fault
430High or low system water pressure
443Low water cut-off (LWCO) activated
520Gas solenoid valve circuit – flame after valve close
540High exhaust (flue gas) temperature
610Combustion fan motor speed fault
700PC Board fault
710Gas solenoid circuit – valve position mismatch
720Flame rod fault
7630-10V external control input over-voltage
831Indirect tank call running too long
890Freeze condition detected
999PC Board / software mismatch
FFFMaintenance performed marker
SSService Soon reminder

Rinnai Combi Boiler error codes

CodeMeaning
021DHW continuous operation time exceeded
100Air intake/exhaust blockage or full condensate trap
110Ignition failure
120Flame failure (flame lost during operation)
140Overheat switch tripped (heat exchanger overheating)
150Venturi control fault
161High DHW outgoing water temperature
170Venturi blockage / position mismatch
180Gas valve air/fuel adjustment limit reached
190Electrical grounding / short in DC circuit
210Data transfer error
220Gas valve position not detected (reed switch)
250Condensate pump switch tripped (accessory)
303Secondary system thermistor fault
310Freeze protection thermistor fault
321Outgoing (DHW) water temperature thermistor fault
331Plate heat exchanger thermistor fault (DHW)
341DHW inlet thermistor fault
353CH supply thermistor fault
363CH return thermistor fault
380Exhaust thermistor fault
393Outdoor temperature sensor fault
400Water pressure sensor communication fault
430High or low system water pressure
443Low water cut-off (LWCO) activated
520Gas solenoid valve circuit – flame after valve close
540High exhaust (flue gas) temperature
610Combustion fan motor speed fault
631DHW recirculation pump – insufficient flow
651Water flow control valve fault
661Bypass valve fault
670Three-way valve fault
681DHW supply temperature abnormality
700PC Board fault
710Gas solenoid circuit – valve position mismatch
720Flame rod fault
7630-10V external control input over-voltage
890Freeze condition detected
999PC Board / software mismatch
FFFMaintenance performed marker
LCLime condition – flush plate heat exchanger
SSService Soon reminder

Rinnai Tankless Water Heater error codes

CodeMeaning
02Burner did not operate during freeze protection
03Power interrupted during bath fill
05Bypass flow control device fault
07Circulation flow rate below 2.1 GPM
10Air supply or exhaust blocked / condensate trap full
11No ignition
12Flame failure
13Combustion fault
14Thermal fuse or overheat sensor tripped
15Venturi control fault
16Outlet water over-temperature safety shutdown
17Venturi blockage
18Gas valve air/fuel adjustment limit reached
19Electrical grounding / DC circuit short
21PC board data transfer error
22Gas valve adjustment fault
25Condensate pump failure or clogged drain
30Flammable vapor sensor activated or faulty
31Burner thermocouple out of range
32Outlet water temperature thermistor fault
33Heat exchanger thermistor fault
34Combustion air thermistor (Non-SENSEI) / Lime detecting thermistor (RX/CX)
35Tank temperature sensor fault
38Exhaust gas temperature sensor (CO sensor on RH180)
41Freeze protection / outdoor air temperature sensor fault
51Inlet water temperature thermistor fault
52Gas valve / modulating solenoid valve (POV) signal fault
54High exhaust gas temperature
57Burner overheat bi-metal switch open
58Secondary heat exchanger bi-metal switch open
61Combustion fan motor fault
63Recirculation low flow
65Water flow control device (servo) fault
66Bypass flow servo fault
70PC board fault
71Gas solenoid valve fault (SV0–SV4 on Non-SENSEI)
72Flame rod fault
73Burner thermocouple fault
79Water leakage detected
FEFlammable vapors detected
FFMaintenance performed (history marker)
LCScale build-up in heat exchanger (LC, LC0–LC9, 00)
SECascade diagnostic display (error on secondary unit)
SEtInitial settings not yet confirmed
SSService Soon alert (also listed as 55)

Rinnai Wall Furnace error codes

CodeMeaning
11No ignition
14Overheat (fusible link)
16Room overheat (above 104°F / 40°C)
30Overheat temperature thermistor 2 open circuit
31Room temperature thermistor open circuit
32Room temperature thermistor short circuit
33Overheat thermistor 1 open circuit
34Overheat thermistor 1 short circuit
35Overheat temperature thermistor 2 short circuit
40Pressure sensor sensing tube failure
49Pressure sensor breakdown
53Abnormal spark sensed
61Combustion fan fault
62Convection fan fault
70ON/OFF or Set Back switch fault
71Solenoid valve failure
72Flame rod failure
73Communication error
99Flue blocked

Find codes by Rinnai model

Non-SENSEI

C199eC199iR50LSiR63LSe2R75LSeR75LSiR94LSeR94LSiR98LSeR98LSe-ASMER98LSiR98LSi-ASMERC80eRC80iRC98eRC98iRE140eRE140iRE160eRE160iRE180eRE180iRE199eRE199iREP160eREP160iREP199eREP199iRL75eRL75e(A)RL75iRL75i(A)RL94eRL94iRLX94iRU80eRU80iRU90eRU98eRU98iRUC80iRUC90iRUC98iRUCS65iRUCS75iRUR98eRUR98iRUS65eRUS75eV53DeV53eV65eV65iV75eV75iV94eV94iV94Xi

SENSEI

CU160eCU160iCU199eCU199iRSC160eRSC160iRSC199eRSC199iRU130eRU130iRU160eRU160iRU180eRU180iRU199eRU199iRUR160eRUR160iRUR199eRUR199i

SENSEI RX/CX

CX160iCX199iCXP160iCXP199iRX130iRX160iRX180iRX199iRXP160iRXP199i

EX DT

EX08DTEX11DTEX17DTEX22DTEX22DT-W

I-Series Plus 150K and smaller

IP060SIP060160CIP090SIP090099CIP090160CIP090199CIP120SIP150SIP120199CIP150199C

I-Series Plus 175K and higher

IP175SIP199SIP175199CIP199199C

RH180 hybrid

RH180

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.

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