Rinnai parts are sold through licensed installers and Rinnai dealers, not direct-to-homeowner. Amazon and large plumbing distributors stock the high-volume parts (flame rods, igniters, isolation valves) and these are DIY-replaceable. Internal parts (heat exchanger, gas valve, control board) are dealer-installed only.
The Rinnai parts catalog
- Heat exchanger — primary failure mode after 10-15 years on scaled units. Dealer-installed.
- Flame rod (flame sensor) — the single most-replaced part. Behind 60% of Code 12 faults. DIY-cleanable, dealer-replaceable.
- Igniter — direct spark ignition assembly. Common Code 11 cause on older units. DIY-replaceable.
- Gas valve — modulating solenoid valve. Dealer-only replacement.
- Control board (PCB) — model-specific. Includes pre-flashed firmware. Dealer-installed.
- Thermocouple — legacy V-series and R-series only. Newer units use spark ignition (no thermocouple).
Where to buy
- Amazon — flame rods, igniters, isolation valves, drain valves, condensate traps
- Rinnai dealer / distributor — Ferguson, Hajoca, Winsupply have Rinnai inventory. Walk-in if you have an account, otherwise through your installer
- Rinnai America direct — for warranty replacement only. Parts shipped to the registered installer, not the homeowner
- OEM-equivalent on Amazon — non-Rinnai brands sell drop-in replacement flame rods and igniters. Functionally identical but voids the warranty if used inside warranty period
Identifying the right part
Rinnai parts are usually model-specific or chassis-specific. Have the model number AND part number from the parts diagram before ordering. Generic "Rinnai flame rod" listings on Amazon are often incompatible across model lines.
- Get the parts diagram from rinnai.us → your model → Manuals → Parts Diagram
- OR call 1-800-621-9419 with the serial number and tell them the symptom
Common multi-part repair kits
- Annual maintenance kit: flame rod + gasket + air inlet filter. ~$50
- Ignition rebuild kit: flame rod + igniter + gasket set. ~$80-120
- Condensate trap rebuild: trap + neutralizer media. ~$60
Warranty considerations
Rinnai's parts warranty (5 years on Sensei) covers OEM Rinnai parts. Using non-OEM parts during warranty period voids the warranty on the affected system. Out of warranty, OEM-equivalent is fine and cheaper.
Bottom line
Flame rod and igniter are routine DIY replacements with the right model-specific part numbers. Anything else, including internal heat exchanger work, goes through a Rinnai-trained installer to keep your warranty intact. See dealers hub for installer locator.