Heat pumps · Error codes · Atlantic
IF-31Atlantic
IF-31 on an Atlantic heat pump: Indoor unit power supply abnormal
Short answer
On an Atlantic heat pump, IF-31 means: Indoor unit power supply abnormal. The heat pump stops until the fault clears or is reset. An engineer is needed to fix the cause.
Reviewed 23 September 2026 · 2 sources
What it means
The manual says: Indoor unit power supply abnormal.
Likely causes:
- Power supply abnormality or outdoor/indoor PCB, inverter or IPM fault.
Is it safe?
| Does the heat pump stop? | Yes |
|---|---|
| Severity | Fault — clears by itself when the condition goes |
| Engineer needed? | Yes |
The heat pump stops until the fault clears or is reset.
What you can check
- Check the heat pump isolator and consumer-unit breakers are on (do not open any casing).
- Note the error number/LED pattern shown and give it to your installer.
- If breakers trip repeatedly, leave the unit off and call an engineer.
What the engineer will check
- Check supply voltage, PCB, inverter/IPM/PFC components and connectors.
Who to ask for: electrical / heat pump.
Certification: Qualified electrician / heat pump engineer.
What you might notice
Sources
- alféa excellia duo Maintenance Document (U0546279_1738_EN_16) ↗ · U0546279_1738_EN_16 · page 69 · Reviewed 23 September 2026
- alféa extensa + Installation and operating manual (doc 1734-10, 1734-EN) ↗ · 1734-10 · page 75 · Reviewed 23 September 2026
A code explains what the controller detected, not a confirmed root cause.
Reviewed: 23 September 2026