H76 on a Dimplex LA MI inverter outdoor air-to-water: Communication fault between indoor control screen and heat pump (remote control error)
Short answer
On a Dimplex heat pump, H76 means: Communication fault between indoor control screen and heat pump (remote control error). 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: Communication fault between indoor control screen and heat pump (remote control error).
Part involved: Remote control panel / cable / main water PCB.
When it shows: Indoor-remote control error during standby or operation.
Likely causes:
- Damaged control cable (often rodents).
- Faulty remote control.
- Faulty main water PCB.
Is it safe?
| Does the heat pump stop? | Yes |
|---|---|
| Engineer needed? | Yes |
The heat pump stops until the fault clears or is reset.
Resetting itself: unknown.
Manual reset: Clear via control panel per Dimplex article (method shown as image).
What you can check
- Note the code and contact the installer or Dimplex service.
What the engineer will check
- Isolate the heat pump from mains before any work.
- Continuity-test each core of the multi-core cable.
- Check 5 V DC at CN-REMOTE2.
Who to ask for: heat pump service engineer / heating engineer.
Certification: Electrical competence (Part P / qualified electrician) for work inside control panels.
What you might notice
Sources
- GDHV Help Centre article: i have h76 error on my la mi heat pump what does this mean ↗ · GDHV article (modified 2023-02) · page n/a (web article) · Reviewed 23 September 2026
A code explains what the controller detected, not a confirmed root cause.
Reviewed: 23 September 2026