Heat pumps · Error codes · Climaveneta / De Longhi Professional
A120Climaveneta / De Longhi Professional · De'Longhi Professional / Climaveneta i-KI MTD / i-KIR MTD DC-inverter air/water heat pump
A120 on a Climaveneta / De Longhi Professional De'Longhi Professional / Climaveneta i-KI MTD / i-KIR MTD DC-inverter air/water heat pump: Water temperature too high in mixed circuit, expansion module 3
Short answer
On a Climaveneta / De Longhi Professional heat pump, A120 means: Water temperature too high in mixed circuit, expansion module 3. The manual does not say whether the heat pump stops. An engineer is needed to fix the cause.
Reviewed 23 September 2026 · 1 source
What it means
The manual says: Water temperature too high in mixed circuit, expansion module 3.
Likely causes:
- Condition described in code text.
Is it safe?
| Does the heat pump stop? | Not stated |
|---|---|
| Engineer needed? | Yes |
The manual does not say whether the heat pump stops.
Resetting itself: Reset from room controller: press the two indicated buttons 3 s, select and confirm reset (p57).
What you can check
- Note the code/LED pattern and the model from the rating plate, then contact a heat pump/refrigeration engineer.
- Check the heat pump's breaker/isolator at the consumer unit is on.
What the engineer will check
- Investigate per manual.
Who to ask for: refrigeration / heat pump engineer.
Certification: Electrical competence for work inside the unit.
What you might notice
Sources
- Climaveneta i-KI MTD / i-KIR MTD (i-EM2 / i-EMR2) 0011m-0061m Installation - User - Maintenance Manual (EN 10/2010) ↗ · EN 10/2010 · page 58 · Reviewed 23 September 2026
A code explains what the controller detected, not a confirmed root cause.
Reviewed: 23 September 2026