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Heat pumps · Error codes · Ideal Heating
385Ideal Heating · Logic Air

385 on an Ideal Heating Logic Air: Low Mains Voltage Fault

Short answer

On an Ideal Heating heat pump, 385 means: Low Mains Voltage Fault. 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: Low Mains Voltage Fault.

Part involved: mains supply.

Likely causes:

  • Low mains supply voltage; local generator not supplying 230 Vac.

Is it safe?

Does the heat pump stop?Not stated
Engineer needed?Yes

The manual does not say whether the heat pump stops.

What you can check

  • Note the code or fault message shown on the controller/Halo and when it appeared; check the heat pump's isolator and consumer-unit breaker are on. Check whether lights or other appliances are also affected (possible supply problem) and whether any breaker/RCD has tripped - do not reset repeatedly.

What the engineer will check

  • Verify supply voltage; if generator in use ensure it supplies 230 Vac; otherwise contact electricity provider.

Who to ask for: Heat pump / heating controls engineer.

Certification: Electrical work by competent person.

Sources

A code explains what the controller detected, not a confirmed root cause.

Reviewed: 23 September 2026