Verified boiler fault code

Worcester Bosch d5 Fault Code (Greenstar FS CDi ErP Regular)

Condensate pump fault.

Safety disclaimer

Boiler repair help from Aza & Sons Services

Fault code summary

Manufacturer
Worcester Bosch
Fault code
d5
Fault type
Condensate
Severity
Not specified
Reset
Not specified
Applicable models
Greenstar FS 30CDi ErP Regular, Greenstar FS 42CDi ErP Regular

Quick answer

Condensate pump fault.

What does this fault code mean?

Condensate pump fault.

Common causes

  • Fault in the condensate pump.

Symptoms

This information was not provided in the verified manufacturer source.

What can the homeowner safely check?

This information was not provided in the verified manufacturer source.

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 the condensate pump and its controls.

Applicable boiler models

Related fault codes

Manufacturer documentation

Greenstar FS 30CDi & 42CDi ErP Regular user instructions

d5 | Condensate pump fault

Last verified

2026-09-12

Frequently asked questions

What does Worcester Bosch d5 mean?

Condensate pump fault.