low-pressure-collector-circuit on an IVT Greenline HE: If Alarm at low pressure in collector circuit is selected and the external input closes, this alarm is triggered. The compressor stops (Æ Chapter 16.6 )
Short answer
On an IVT heat pump, low-pressure-collector-circuit means: If Alarm at low pressure in collector circuit is selected and the external input closes, this alarm is triggered. The compressor stops (Æ Chapter 16.6 ). 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: If Alarm at low pressure in collector circuit is selected and the external input closes, this alarm is triggered. The compressor stops (Æ Chapter 16.6 ).
When it shows: If Alarm at low pressure in collector circuit is selected and the external input closes, this alarm is triggered. The compressor stops (Æ Chapter 16.6 ).
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.
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. Look at the brine expansion tank: the fluid level should be visible (user guide check). Do not refill or open the ground-loop circuit yourself - call the installer.
What the engineer will check
- Investigate per the installer guide alarm description and operating data.
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.67; 6 720 643 409 p.82; 6 720 643 415 p.26 · Reviewed 23 September 2026
A code explains what the controller detected, not a confirmed root cause.
Reviewed: 23 September 2026