Biasi Parva 28S Fault codes & diagnostics

2 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.

Combi Natural Gas 28 kW 2001 onwards Discontinued
GC Number 47-970-14
Download the Biasi Parva 28S manual The official installation & service manual (PDF) — the exact document these fault codes were verified against. PDF

The fault code is already on your display

Note it down before pressing reset — resetting clears the code immediately. How to read fault codes →

Versions & GC numbers

Which version do you have?

The GC number on your boiler's data badge identifies the exact appliance and production years, as recorded in the UK Product Characteristics Database.

GC number Appliance (register name) Produced
47-970-14 Parva M90 28S 2001–present
Fault codes

All 2 documented codes

Tap any card for details

ER + 69

Your boiler has detected an electrical communication problem or a wiring fault within its internal control system.

High Engineer only £120-350 Shared across the range

Parts commonly replaced

  • Main PCB
  • Wiring Harness
Full explanation for ER + 69
LP

Your boiler has detected that the water pressure is too low to operate safely.

High DIY-safe £0-120 Shared across the range

What to check first

  1. Locate the filling loop valves underneath the boiler.
  2. Slowly open both taps to let fresh water into the system.
  3. Watch the pressure gauge and close the taps once the needle reaches between 1 and 1.5 bar.

Parts commonly replaced

  • Filling loop
  • Water pressure switch
  • Expansion vessel
Full explanation for LP
Status & diagnostic codes

5 operating states & engineer diagnostics

Not faults — these are normal operating states. Tap to expand.

30c Diagnostic Your boiler has likely detected a sensor problem that is preventing it from heating your water correctly. G20 Diagnostic Your boiler is correctly configured for the standard natural gas supply used in UK homes. G30 Diagnostic Your boiler is currently configured for a specific type of bottled gas (Butane) rather than the standard mains gas supply, and it cannot safely operate in its current mode. G31 Diagnostic Your boiler is currently configured for propane gas but is not receiving the correct pressure or supply to operate safely. Li Status Your boiler has failed to ignite after several attempts, meaning it cannot produce heat or hot water.