electric-additional-heat-shut-down-due-to-high-temperature-e2x-t8 on an IVT Greenline HE: The electric heater is turned off. The warning is activated in additional heat mode if the sensor T8 exceeds 80 °C
Short answer
On an IVT heat pump, electric-additional-heat-shut-down-due-to-high-temperature-e2x-t8 means: The electric heater is turned off. The warning is activated in additional heat mode if the sensor T8 exceeds 80 °C. The heat pump keeps running with some functions stopped. An engineer is needed to fix the cause.
Reviewed 23 September 2026 · 1 source
What it means
The manual says: The electric heater is turned off. The warning is activated in additional heat mode if the sensor T8 exceeds 80 °C.
Part involved: E2x.T8.
When it shows: The electric heater is turned off. The warning is activated in additional heat mode if the sensor T8 exceeds 80 °C.
Is it safe?
| Does the heat pump stop? | Partly |
|---|---|
| Severity | Warning |
| Engineer needed? | Yes |
The heat pump keeps running with some functions stopped.
Resetting itself: Yes - The warning is deactivated when T8 falls below 76 °C.
What you can check
- Note the full alarm text including the component designation (e.g. E21.T6) - IVT asks for it when you contact the dealer. Contact the dealer if the warning recurs often. Check the heating-system pressure gauge is in the range given in the user guide - do not top up yourself unless you have been shown how; check radiator/underfloor valves and room thermostats are open.
What the engineer will check
- Reset overheat protection / check electric heater and its supply.
Who to ask for: heat pump engineer.
What you might notice
Sources
- Installer Guide Greenline HE C6-C11 E6-E11 1x230V (6 720 802 419 (2012/06) en) ↗ · 6 720 802 419 (2012/06) · page 6 720 802 419 p.70; 6 720 643 409 p.88; 6 720 643 415 p.32 · Reviewed 23 September 2026
A code explains what the controller detected, not a confirmed root cause.
Reviewed: 23 September 2026