Heat pumps · Error codes · Climaveneta / De Longhi Professional
Er03Climaveneta / De Longhi Professional · De'Longhi Professional / Climaveneta AWR MTD reverse-cycle air/water heat pump with DHW
Er03 on a Climaveneta / De Longhi Professional De'Longhi Professional / Climaveneta AWR MTD reverse-cycle air/water heat pump with DHW: High pressure alarm from pressure transducer
Short answer
On a Climaveneta / De Longhi Professional heat pump, Er03 means: High pressure alarm from pressure transducer. The heat pump stops until the fault clears or is reset. An engineer is needed to fix the cause.
Reviewed 23 September 2026 · 1 source
What it means
The manual says: High pressure alarm from pressure transducer.
Likely causes:
- High discharge pressure.
Is it safe?
| Does the heat pump stop? | Yes |
|---|---|
| Engineer needed? | Yes |
The heat pump stops until the fault clears or is reset.
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.
- Check the outdoor unit is not blocked by leaves, snow or debris.
What the engineer will check
- Check high discharge pressure.
- Check transducer and wiring.
Who to ask for: refrigeration / heat pump engineer.
Certification: F-gas certification (refrigerant circuit work) and electrical competence.
What you might notice
Sources
- Climaveneta AWR MTD / AWR MTD/B 0011-0061 Installation - Operating - Service Manual (GB 01/2009) ↗ · GB 01/2009 · page 47 · Reviewed 23 September 2026
A code explains what the controller detected, not a confirmed root cause.
Reviewed: 23 September 2026