Heat pumps · Error codes · Danfoss
com-error-hub-cardDanfoss · DHP-AQ
com-error-hub-card on a Danfoss DHP-AQ: Communication broken between display card and hub card (indoor)
Short answer
On a Danfoss heat pump, com-error-hub-card means: Communication broken between display card and hub card (indoor). 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: Communication broken between display card and hub card (indoor).
Part involved: display card - hub card link.
Likely causes:
- Communication cable/connection or card fault.
Is it safe?
| Does the heat pump stop? | Yes |
|---|---|
| Engineer needed? | Yes |
The heat pump stops until the fault clears or is reset.
Manual reset: Set operating mode OFF then back to the desired mode.
What you can check
- Note the exact alarm text. The manual allows acknowledging by setting operating mode OFF then back once; if the alarm returns, call an engineer.
What the engineer will check
- Check/replace communication cable; test cards.
Who to ask for: heat pump engineer.
Certification: Qualified electrician / heat pump engineer (electrical fault-finding).
What you might notice
Sources
- Service Instructions DHP-AQ (VMGFJ202) ↗ · VMGFJ202 · page p.10 · Reviewed 23 September 2026
A code explains what the controller detected, not a confirmed root cause.
Reviewed: 23 September 2026