Truma Water Heater: “W31”
info RV water heater fault codes
What it means
Decalcification finished. A status message confirming the unit has completed its routine descaling (decalcification) maintenance cycle. Not a fault.
Most likely causes
- Decalcification/descaling cycle completed normally most likely
Safe checks you can do yourself
- No action needed; this confirms maintenance completed
- Flush the unit per the manual after descaling so no cleaning agent remains before normal use
How to reset / clear W31
- Return the unit to eco or comfort mode to clear the message and resume normal operation
When to call a technician
Not applicable; this is a normal completion message.
Applies to
Truma AquaGo comfort · Truma AquaGo comfort plus
FAQ
What does Truma Water Heater code "W31" mean?
Decalcification finished. A status message confirming the unit has completed its routine descaling (decalcification) maintenance cycle. Not a fault.
How do I reset Truma Water Heater W31?
Return the unit to eco or comfort mode to clear the message and resume normal operation
What is the most common cause of W31 on a Truma Water Heater?
The most likely cause is decalcification/descaling cycle completed normally.
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Sources
- Tech Tip: Truma AquaGo Error Codes — Truma US official tech tip, code W31 decalcification finished (Truma (manufacturer))
- Truma AquaGo basic Operating Instructions — Appendix A Error Codes — Operating Instructions Appendix A, Error Codes table (Truma / ManualsLib)
Note: Decalcification is a feature of comfort/comfort plus models; the basic model does not run this cycle.
● Last verified 2026-06-29 · compiled from manufacturer documentation. Codes can vary by model year — always cross-check your unit’s manual.