Heat pumps · Error codes · IVT
POWER-FAILUREIVT · Greenline HT Plus
POWER-FAILURE on an IVT Greenline HT Plus: Power failure: one or two phases to the heat pump are down
Short answer
On an IVT heat pump, POWER-FAILURE means: Power failure: one or two phases to the heat pump are down. 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: Power failure: one or two phases to the heat pump are down.
Part involved: incoming supply.
Likely causes:
- One or two phases down (house fuses blown / MCBs tripped). The heat pump keeps its settings and restarts automatically ~15 min after power returns.
Is it safe?
| Does the heat pump stop? | Yes |
|---|---|
| Severity | Fault — clears by itself when the condition goes |
| Engineer needed? | Yes |
The heat pump stops until the fault clears or is reset.
Resetting itself: Yes.
What you can check
- Check the heat pump's breaker/isolator at the consumer unit is on and has not tripped. Check the house fuses/breakers supplying the heat pump; reset a tripped breaker once. The heat pump returns to operation automatically 15 minutes after the fault is rectified.
What the engineer will check
- Check all three phases at the heat pump; investigate supply.
Who to ask for: heat pump engineer.
Certification: Qualified electrician / heat pump engineer (electrical fault-finding).
What you might notice
Sources
- Greenline HT Plus C and E Guide to installation, commissioning and maintenance (Art. no 290410-29, v1.1) ↗ · 290410-29 v1.1 · page p.32 (installer guide), p.37 (user guide printed) · Reviewed 23 September 2026
A code explains what the controller detected, not a confirmed root cause.
Reviewed: 23 September 2026