Heat pumps · Error codes · iDM Energiesysteme
170iDM Energiesysteme · TERRA SW (2013)
170 on an iDM Energiesysteme TERRA SW: Sensor fault: Heat pump return sensor (B34) - short circuit
Short answer
On an iDM Energiesysteme heat pump, 170 means: Sensor fault: Heat pump return sensor (B34) - short circuit. The manual does not say whether the heat pump stops. An engineer is needed to fix the cause.
Reviewed 23 September 2026 · 1 source
What it means
The manual says: Sensor fault: Heat pump return sensor (B34) - short circuit.
Part involved: Heat pump return sensor (B34).
Likely causes:
- Short-circuited sensor or sensor cable.
Is it safe?
| Does the heat pump stop? | Not stated |
|---|---|
| Severity | Fault — clears by itself when the condition goes |
| Engineer needed? | Yes |
The manual does not say whether the heat pump stops.
What you can check
- Note the fault number shown after tapping the fault symbol. If it persists, contact iDM service/your installer.
What the engineer will check
- Measure sensor and cable resistance; check terminal connection on Navigator board; replace sensor/cable.
Who to ask for: heat pump engineer.
What you might notice
Sources
- IDM Wärmepumpen mit Navigatorregelung 2.0 - Bedienungsanleitung (812152 Rev.3) ↗ · 812152 Rev.3 · page p.69 · Reviewed 23 September 2026
A code explains what the controller detected, not a confirmed root cause.
Reviewed: 23 September 2026