Gas valve fault
Displayed as: 52
Rinnai's RU series installation and operation manual lists diagnostic code 52 as "Gas Valve". The manual's checks are: check the flame rod and wire for damage, check the gas solenoid valve for an open or short circuit, replace the gas valve assembly, and contact the Rinnai technical department if the fault persists.
If you smell gas
- Stop what you are doing. Do not use phones, switches, matches or anything that can spark inside.
- Go outside and leave the door open behind you.
- Call the FortisBC 24-hour emergency line at 1-800-663-9911 or dial 911.
Only after that, call CANRO about the water heater. Official guidance: FortisBC gas leaks and odour.
Applies to
This code and wording come from manual 100000467 for the RU series. The cross-series document 100000652 applies the same code across SENSEI and non-SENSEI generations.
- Rinnai SENSEI RU (Super High Efficiency Plus condensing)
- Rinnai RU130iN
- Rinnai RU160iN
- Rinnai RU180iN
- Rinnai RU199iN
Control platform: Rinnai PC board with digital controller display. Source manual: 100000467 (rev. 07 on rinnai.ca) (2020–2021).
Why a code is not a diagnosis
The control has detected a problem in the gas-valve circuit or in the flame-sensing path that the valve depends on. The manual's order matters: the flame rod and its wire are checked first because a damaged sensing circuit can mimic a valve fault, and the valve assembly is replaced only after that.
Same code, other equipment
- Rinnai non-SENSEI series: Same code family per troubleshooting document 100000652. Source
Safe things to observe
- Note whether the code returns immediately after a reset or only when the unit tries to fire.
- If you smell gas at any point, leave the building and call FortisBC at 1-800-663-9911 or 911.
Do not
- Do not reset repeatedly to force the burner on.
- Do not bypass or jumper the gas valve circuit.
- Do not attempt to disassemble the gas valve assembly.
How professional service helps
- A technician checks the flame rod and wire, tests the gas solenoid valve for open or short circuits, and replaces the valve assembly per the manual.
- The Rinnai technical department is involved where the fault persists after replacement, as the manual directs.
Diagnostic visit
Repair visits carry a diagnostic service fee that CANRO states is credited toward the repair if you proceed. The amount is confirmed by phone; it is not published. Source, checked September 7, 2026.
Where CANRO provides on-site service
On-site service is currently offered across Metro Vancouver: Vancouver, Burnaby, Richmond, Surrey, Coquitlam, North Vancouver, West Vancouver, New Westminster, Delta, Langley, Port Moody, Port Coquitlam, Maple Ridge, Pitt Meadows, White Rock, Tsawwassen; plus Anmore, Belcarra, Lions Bay, Bowen Island, Abbotsford with travel or ferry arrangements confirmed by phone. Everything else on this site is reference information you can use anywhere in Canada.
Frequently asked questions
Does code 52 mean the gas valve is definitely broken?
Not yet. The manual checks the flame rod and its wiring first, then tests the solenoid valve, and replaces the valve assembly only if those checks point at it.
Is code 52 dangerous?
The unit is locked out, which is the safe direction. Gas smell is a separate emergency regardless of the code: leave and call FortisBC or 911.
Locked out with no hot water? Call with the code ready.
The brand, model and this code are passed along when you request service online, so the technician arrives prepared.
On-site service in Metro Vancouver, BC. Call to check availability.
Sources and verification
- Rinnai RU series Installation and Operation Manual, section 5.6 Diagnostic Codes · 100000467 · accessed September 7, 2026
Facts checked September 7, 2026. Last updated September 7, 2026. Technical reviewer: not yet assigned.