faulty-electric-heater-e21-e2 on an IVT Greenline HE: The electric heater is turned off. Activated by tripped overheat protection on the electric additional heat, high flow temperature or too high temperature in electric additional heat. The automatic trip fuse to the electric additional heat may have been tripped due to, for example, a short circuit
Short answer
On an IVT heat pump, faulty-electric-heater-e21-e2 means: The electric heater is turned off. Activated by tripped overheat protection on the electric additional heat, high flow temperature or too high temperature in electric additional heat. The automatic trip fuse to the electric additional heat may have been tripped due to, for example, a short circuit. 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. Activated by tripped overheat protection on the electric additional heat, high flow temperature or too high temperature in electric additional heat. The automatic trip fuse to the electric additional heat may have been tripped due to, for example, a short circuit.
Part involved: E21.E2.
When it shows: The electric heater is turned off. Activated by tripped overheat protection on the electric additional heat, high flow temperature or too high temperature in electric additional heat. The automatic trip fuse to the electric additional heat may have been tripped due to, for example, a short circuit.
Is it safe?
| Does the heat pump stop? | Partly |
|---|---|
| Severity | Fault — needs a manual reset once the cause is fixed |
| Engineer needed? | Yes |
The heat pump keeps running with some functions stopped.
Manual reset: Acknowledge on control panel.
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 alarm remains after acknowledgement. Acknowledge once on the control panel; if the alarm returns, contact the installer.
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.68; 6 720 643 409 p.84; 6 720 643 415 p.28 · Reviewed 23 September 2026
A code explains what the controller detected, not a confirmed root cause.
Reviewed: 23 September 2026