Rinnai 25: Condensate Drain Fault
What the Rinnai 25 error code means, what causes it, and why it's a job for a licensed BC gas technician — not a DIY reset.
Severity
Moderate — book a service visit
What the Rinnai 25 error code means
Condensate is not draining properly, or water was detected where it should not be.
On Rinnai i-Series, M-Series and Q-Series, 25 is a condensate fault. It is a protective response — the boiler is telling you something needs attention, and the safe, lasting fix is a proper diagnosis rather than repeated resets.
Symptoms you may notice
- Lockout, often after very cold weather
- Water pooling near the boiler
- Gurgling sounds from the trap
Common causes of Rinnai 25
Why this is not a DIY fix
Condensing boilers produce acidic condensate that must drain freely. A blocked or frozen condensate trap/line backs water into the boiler and trips a safety lockout. Clearing and correctly re-routing or protecting the line is best done by a technician to prevent repeats.
In British Columbia, gas work must be performed by a TSBC-licensed gas fitter. GasBoilers.ca — a CanroHeat division — sends Red Seal–certified, gas-licensed technicians who diagnose the true cause, repair it correctly, and verify safe operation before they leave.
How our technicians diagnose & repair it
- 1Clear and clean the condensate trap and drain line
- 2Check for frozen, sagging or improperly sloped runs
- 3Verify the neutraliser (where fitted) is not exhausted
- 4Re-route or add freeze protection to prevent recurrence
Related Rinnai codes
Rinnai 25 — FAQ
What does the Rinnai 25 error code mean?
Condensate is not draining properly, or water was detected where it should not be. On Rinnai i-Series, M-Series and Q-Series, this is categorised as a condensate fault.
What causes Rinnai 25?
The most common causes are: Blocked condensate trap/line; Frozen condensate line; Improper slope. A licensed technician confirms which one applies before any part is replaced.
Can I fix Rinnai 25 myself?
No. Condensing boilers produce acidic condensate that must drain freely. A blocked or frozen condensate trap/line backs water into the boiler and trips a safety lockout. Clearing and correctly re-routing or protecting the line is best done by a technician to prevent repeats. Repeatedly resetting the boiler without fixing the root cause can be unsafe and can cause further damage. Call GasBoilers.ca at 604-359-1081 for a licensed diagnosis.
Is the Rinnai 25 error code dangerous?
This is a protective fault — the boiler has shut down a function to protect itself. It is best diagnosed promptly by a licensed technician so the underlying cause does not lead to a more expensive failure.
How much does it cost to fix Rinnai 25 in Greater Vancouver?
Cost depends on the root cause and any parts needed. We start with a flat-rate diagnostic, then quote the repair before any work begins — no surprises. Call 604-359-1081 for current pricing and same-day availability.
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Rinnai showing 25? We'll fix it right.
Licensed, Red Seal–certified gas technicians across Greater Vancouver. Upfront pricing, same-day service available.