Heat pumps · Error codes · Warmflow
NO-LINKWarmflow · Zeno G-Series ground source heat pump GS08/GS16/GS03
NO-LINK on a Warmflow Zeno G-Series ground source heat pump GS08/GS16/GS03: NO LINK (user interface not communicating)
Short answer
On a Warmflow heat pump, NO-LINK means: NO LINK (user interface not communicating). The manual does not say whether the heat pump stops.
Reviewed 23 September 2026 · 1 source
What it means
The manual says: NO LINK (user interface not communicating).
Part involved: controller/PCB communication.
Likely causes:
- A power surge has caused a fault with the user interface.
- There is a communication problem between the user interface and the main control board.
Is it safe?
| Does the heat pump stop? | Not stated |
|---|
The manual does not say whether the heat pump stops.
What you can check
- Per the GS03 manual (user action): isolate the power to the unit using the main isolator switch for 2 minutes, then restore the power.
- If 'NO LINK' remains, note it and contact your installer/Warmflow.
What the engineer will check
- Please consult Warmflow.
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
- Warmflow Ground Source Heat Pump G-Series GS03 - User, Installation & Service Instructions (8939 Issue A) ↗ · 8939 Issue A · page 55 · Reviewed 23 September 2026
A code explains what the controller detected, not a confirmed root cause.
Reviewed: 23 September 2026