L.757 on a Glow-worm GeniaAir: The heat pump has fallen below the minimum running time for the compressor. The unit continues to operate. If the minimum running time is repeatedly not reached, operation is stopped in order to protect the compressor
Short answer
On a Glow-worm heat pump, L.757 means: The heat pump has fallen below the minimum running time for the compressor. The unit continues to operate. If the minimum running time is repeatedly not reached, operation is stopped in order to protect the compressor. The heat pump keeps running with some functions stopped.
Reviewed 23 September 2026 · 1 source
What it means
The manual says: The heat pump has fallen below the minimum running time for the compressor. The unit continues to operate. If the minimum running time is repeatedly not reached, operation is stopped in order to protect the compressor.
Part involved: The heat pump has fallen below the minimum running time for the compressor. The.
Likely causes:
- The heat pump has fallen below the minimum running time for the compressor. The unit continues to operate. If the minimum running time is repeatedly not reached, operation is stopped in order to protect the compressor.
Is it safe?
| Does the heat pump stop? | Partly |
|---|---|
| Severity | Warning |
The heat pump keeps running with some functions stopped.
Resetting itself: yes - reversible L-codes eliminate themselves; the unit attempts to restart.
Manual reset: not required.
What you can check
- Note the full code and text shown on the display (and the date/time it appeared). The unit restarts by itself; if the code keeps appearing, or an F-code follows, contact your installer.
What the engineer will check
- Monitor; if it recurs or turns into the corresponding F-code, diagnose as for that F-code. Corresponding lockout fault: F.757.
Who to ask for: F-gas certified refrigeration engineer with heat pump experience (R290 flammable-refrigerant competence required for aroTHERM plus / GeniaAir).
Certification: F-gas Category I (Regulation (EU) 517/2014 as retained in GB) certificate; flammable (R290) refrigerant training for R290 units.
What you might notice
Sources
- GeniaAir Appliance Interface installation and maintenance instructions ↗ · 8000043014_01 · page HPIM 7 8000043014_01 p.30 · Reviewed 23 September 2026
A code explains what the controller detected, not a confirmed root cause.
Reviewed: 23 September 2026