Verified boiler fault code

Keston 71 Fault Code (Heat 2)

PWM pump dry-run error (80% feedback).

Safety disclaimer

Boiler repair help from Aza & Sons Services

Fault code summary

Manufacturer
Keston
Fault code
71
Fault type
Pump, Circulation
Severity
blocking
Reset
Not specified
Applicable models
Keston Heat 2 45, Keston Heat 2 55, Keston Heat 2 45P, Keston Heat 2 55P

Quick answer

PWM pump dry-run error (80% feedback).

What does this fault code mean?

PWM pump dry-run error (80% feedback).

Common causes

  • PWM pump dry-run feedback error.

Symptoms

  • The boiler fault screen shows code 71 and a blocking condition.

What can the homeowner safely check?

  • Record the code and contact a qualified engineer.

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 pump feedback, pump operation and circulation.

Applicable boiler models

Related fault codes

Manufacturer documentation

Keston Heat 2 Installation & Servicing Manual

FAULT FINDING MENU (continued): PWM pump dry run error (feedback 80%) — code 71.

Last verified

2026-09-12

Frequently asked questions

What does Keston 71 mean?

PWM pump dry-run error (80% feedback).