Heat pumps · Error codes · Trianco
E08iTrianco · Activair Pro (AI) R290 6/12/17kW
E08i on a Trianco Activair Pro R290 6/12/17kW: Communication Fault with Indoor Unit
Short answer
On a Trianco heat pump, E08i means: Communication Fault with Indoor Unit. 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: Communication Fault with Indoor Unit.
Part involved: controller/PCB communication.
Likely causes:
- No successful communication with the indoor unit for 70 continuous seconds while indoor unit control is enabled.
Is it safe?
| Does the heat pump stop? | Not stated |
|---|---|
| Engineer needed? | Yes |
The manual does not say whether the heat pump stops.
What you can check
- Note the exact code shown on the controller (a photo helps) and report it to your installer or the manufacturer's service line.
- Check the heat pump's supply breaker/isolator at the consumer unit is on (do not open any casing).
- Check the controller display is lit and showing the code.
What the engineer will check
- If no indoor unit is installed, modify parameters to disable indoor unit control.
- If installed, inspect communication wiring between indoor unit and heat pump.
Who to ask for: heat pump controls / electrical.
Certification: Electrical competence (Part P / qualified electrician) for work inside control panels.
What you might notice
Sources
- Trianco Activair Pro Air Source Heat Pump (R290 6/12/17kW) - Installation Operation and Service Manual ↗ · 06/2026 · page 41 · Reviewed 23 September 2026
A code explains what the controller detected, not a confirmed root cause.
Reviewed: 23 September 2026