Heat pumps · Error codes · CTC
I030CTC · control system alarm/information platform (error-code grouping)
I030 on a CTC control system alarm/information platform: Driver block under voltage - heat pump stopped due to insufficient mains voltage; will attempt restart
Short answer
On a CTC heat pump, I030 means: Driver block under voltage - heat pump stopped due to insufficient mains voltage; will attempt restart. The heat pump keeps running with some functions stopped.
Reviewed 23 September 2026 · 1 source
What it means
The manual says: Driver block under voltage - heat pump stopped due to insufficient mains voltage; will attempt restart.
Part involved: control system status.
Is it safe?
| Does the heat pump stop? | Partly |
|---|---|
| Severity | Information only |
| Engineer needed? | No |
The heat pump keeps running with some functions stopped.
Resetting itself: Message clears when the condition ends.
What you can check
- Read the message; it is informational.
- Check timer/tariff/holiday/remote-control settings on the controller if heating or hot water is unexpectedly off.
What the engineer will check
- Review installer settings (tariff, SmartGrid, remote control inputs, compressor block, power limitation).
- Check mains supply voltage and inverter driver.
Who to ask for: heat pump controls.
What you might notice
Sources
- CTC EcoZenith i255 Installation and Maintenance Manual (400V 3N~/230V 1N~/230V 3~) ↗ · 162 505 67-9 CR01164 2026-05-10 · page 79 · Reviewed 23 September 2026
A code explains what the controller detected, not a confirmed root cause.
Reviewed: 23 September 2026