716 on an alpha innotec heat pump: High-pressure fault. Please call installer: High-pressure pressostat in the refrigerant circuit has responded several times
Short answer
On an alpha innotec heat pump, 716 means: High-pressure fault. Please call installer: High-pressure pressostat in the refrigerant circuit has responded several times. 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 fault. Please call installer: High-pressure pressostat in the refrigerant circuit has responded several times.
When it shows: High-pressure pressostat in the refrigerant circuit has responded several times.
Likely causes:
- Insufficient heating water flow.
- Overflow valves.
- Temperature.
- Condensation.
Is it safe?
| Does the heat pump stop? | Yes |
|---|---|
| Severity | Fault — needs a manual reset once the cause is fixed |
| Engineer needed? | Yes |
The heat pump stops until the fault clears or is reset.
Resetting itself: no.
Manual reset: manual acknowledgement required (rotary pushbutton 7 s) - display usually says "Please call installer".
What you can check
- Note the error number and text shown on the Luxtronik display.
- Acknowledge the message by pressing the rotary pushbutton for about 7 seconds (as the Luxtronik manual permits); if the same error reappears, contact your installer or ait customer service with the error number.
- Check the heat pump breakers/isolator at the consumer unit are on (do not open any casing).
- Check the heating system pressure gauge reading and report it to the installer.
What the engineer will check
- Check heating water flow.
- Check overflows.
- Check temperature and condensation.
Who to ask for: F-gas certified refrigeration / heat pump engineer (R290 flammable-refrigerant competence for propane units such as LWD).
Certification: F-gas certification (R407C/R410A units); flammable refrigerant training for R290 units.
What you might notice
Sources
- Operating manual Luxtronik heating and heat pump control Part 2 (UK) 83055400lUK - 2.1 ↗ · 83055400lUK 2.1 · page 52 · Reviewed 23 September 2026
A code explains what the controller detected, not a confirmed root cause.
Reviewed: 23 September 2026