Heat pumps · Error codes · Danfoss
heating-circ-pumpDanfoss · DHP-AQ
heating-circ-pump on a Danfoss DHP-AQ: Circulation pump is jammed
Short answer
On a Danfoss heat pump, heating-circ-pump means: Circulation pump is jammed. 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: Circulation pump is jammed.
Part involved: heat pump circulation pump.
Likely causes:
- Air in heating system; jammed pump (after 5 unsuccessful shake attempts).
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: Set operating mode OFF then back to the desired mode.
What you can check
- Note the exact alarm text. Check the heating-system pressure gauge is in the range given in the user guide (Thermia/Danfoss: 1-1.5 bar when cold) - do not top up yourself unless you have been shown how; check radiator/underfloor valves and room thermostats are open. The manual allows acknowledging by setting operating mode OFF then back once; if the alarm returns, call an engineer.
What the engineer will check
- Vent heating system; cut power and manually run pump; repeat; replace pump.
Who to ask for: heat pump engineer.
What you might notice
Sources
- Service Instructions DHP-AQ (VMGFJ202) ↗ · VMGFJ202 · page p.10; p.19 · Reviewed 23 September 2026
A code explains what the controller detected, not a confirmed root cause.
Reviewed: 23 September 2026