Potterton E430 Fault Code (Assure Combi & System)

Safety disclaimer

Fault code summary

Manufacturer

Potterton

Fault code

E430

Fault type

Pressure sensor, Low pressure

Severity

temporary

Reset

Not specified

Applicable models

Potterton Assure Combi, Potterton Assure System

Quick answer

Temporary water-pressure fault.

What does this fault code mean?

Temporary water-pressure fault.

Common causes

• Temporary water-pressure fault.

Symptoms

• The boiler displays E430 and operation may pause.

What can the homeowner safely check?

• Read the pressure gauge/display without removing the casing.

Boiler reset information

Reset information was not provided in the verified manufacturer source. Do not repeatedly reset an unresolved fault.

When should I call an engineer?

Contact a suitably qualified heating engineer when the fault persists, the boiler locks out, or the manufacturer instructions do not resolve it. For gas appliance work in the UK, use a Gas Safe registered engineer.

Engineer diagnosis

• Check system pressure, pressure sensing and the filling system.

Applicable boiler models

• Potterton Assure Combi
• Potterton Assure System

Related fault codes

• E09 — Assure Combi & System

  Gas valve connection fault.

  Read fault code
• E10 — Assure Combi & System

  External probe fault.

  Read fault code
• E109 — Assure Combi & System

  Precirculation alarm.

  Read fault code
• E110 — Assure Combi & System

  The boiler maximum temperature was exceeded, or the safety thermostat sensor tripped.

  Read fault code
• E118 — Assure Combi & System

  Water pressure is low, below 0.5 bar.

  Read fault code
• E12 — Assure Combi & System

  Differential water-flow switch fault; the switch is still open.

  Read fault code
• E125 — Assure Combi & System

  Water circulation fault.

  Read fault code
• E128 — Assure Combi & System

  Safety error for frequent loss of flame.

  Read fault code

Manufacturer documentation

Potterton Assure Combi & System — E430 / 166: Water pressure temporary fault.

Last verified

2026-09-12

Frequently asked questions