Condensate pump fault (accessory)
Displayed as: 25
Rinnai's RU series installation and operation manual lists diagnostic code 25 as "Condensate Pump (Accessory)". The manual's checks are: confirm the wire connections and harness are good, and ensure the condensate reservoir is empty and the condensate pump is operating.
If the water heater is leaking
- Close the cold-water shut-off valve on the pipe feeding the heater, if you can reach it safely.
- Gas unit: turn the gas control to OFF. Electric unit: switch off its breaker. Do not touch electrical parts while standing in water.
- Do not cap or plug the relief-valve discharge pipe, even if that is where the water is coming from.
A leaking tank body cannot be repaired; a dripping relief valve or fitting often can. Call CANRO with a description of where the water appears.
Applies to
This code and wording come from manual 100000467 for the RU series and applies only where the optional condensate pump accessory is installed; units draining condensate by gravity alone have no pump to report. The cross-series document 100000652 applies the code across the 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 code appears when the pump circuit or the pump itself fails to move condensate. The manual's checks split the cause between wiring (connections and harness) and the pump (reservoir full or pump not operating). A pump that cannot clear the reservoir leads to a full trap, which then produces blockage codes, so the two are related.
Same code, other equipment
- Rinnai non-SENSEI series: Same code family per troubleshooting document 100000652. Source
Safe things to observe
- Check the condensate line and reservoir area for water or overflow.
- Note whether the pump runs audibly when the unit calls for it.
Do not
- Do not bypass the pump or disconnect the condensate line to clear the code.
- Do not work on the pump wiring with the unit powered.
How professional service helps
- A technician checks the pump wiring and harness, clears a full reservoir, and tests or replaces the condensate pump per the manual.
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
Why does my unit show code 25 if it drains by gravity?
If no condensate pump accessory is fitted, the code should not appear from the pump; a wiring or board fault can still report it, which is part of the technician's checks.
Can a full condensate reservoir cause other codes?
Yes. A pump that fails to clear the reservoir lets the trap fill, and a full trap produces air-blockage codes. The pump service and trap cleaning go together.
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.