Electrical grounding fault
Displayed as: 19
Rinnai's RU series installation and operation manual lists diagnostic code 19 as "Electrical Grounding". The manual's single check is to check all components for an electrical short, and it cross-references the Electrical Diagnostics on the technical data sheet on the inside front cover of the heater.
Applies to
This code and wording come from manual 100000467 for the RU series. The cross-series document 100000652 applies the same code family across the tankless generations it covers.
- 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 grounding or short-circuit condition somewhere in the unit's electrical system. The manual's check is deliberately broad, because the short can live in any component circuit; the technical data sheet's electrical diagnostics guide the technician component by component.
Same code, other equipment
- Rinnai non-SENSEI series: Same meaning per troubleshooting document 100000652. Source
Safe things to observe
- Confirm the unit is powered from a properly grounded receptacle and that no water is near electrical parts.
- Note whether the code appeared after recent work on the unit or after a power event.
Do not
- Do not reset repeatedly and continue operating a unit with a suspected electrical short.
- Do not open the unit's electrical compartment or test circuits yourself.
- Do not run the unit from an ungrounded or extension-cord supply.
How professional service helps
- A technician follows the technical data sheet's electrical diagnostics to find the shorted circuit, checking supply grounding and each component's wiring, and repairs or replaces the faulted part.
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
Can a bad outlet cause code 19?
A missing or faulty ground at the receptacle is one of the first things checked, since the control relies on a proper earth reference. A qualified electrician or the technician verifies the supply first.
Is it safe to keep resetting code 19?
No. An electrical short can damage the board or components, and the unit is locked out for a reason. Have the circuits tested before returning it to service.
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
- Rinnai Troubleshooting Tankless Water Heater Diagnostic Codes · 100000652 · accessed September 7, 2026
Facts checked September 7, 2026. Last updated September 7, 2026. Technical reviewer: not yet assigned.