Chloe rents out a 3-bed semi in the BB2 postcode of Blackburn to a young family. When the old Worcester Greenstar Junior packed up on the coldest week of February, she called us on a Tuesday afternoon. By Friday afternoon her tenants had hot water again — and a full 10-year Worcester warranty on the new install.
The property
A traditional 1930s 3-bed semi off Preston New Road, BB2. Original combi boiler in the kitchen, one bathroom, low-pressure town mains (about 2.2 bar), and radiators that had never seen a powerflush in the decade Chloe had owned it. Water hardness in BB2 is moderate — around 210 ppm — so scale wasn't the killer, but sludge was.
Why the old boiler failed
Fault code EA229 on a 14-year-old Worcester Junior — a common fan / air-pressure switch failure that's uneconomic to repair on an appliance that's already past its design life. The heat exchanger showed classic sludge staining when we removed the pump, and the diverter valve had visible corrosion.
The fixed-price quote
Chloe had two quotes on the table: £1,850 from a national installer (with a 5-year warranty) and our fixed-price of £2,150 for a Worcester Greenstar 4000 30 kW combi with a full 10-year Worcester warranty, MagnaClean Professional 2 filter, chemical hot flush, new filling loop and CP12 gas safety certificate. She picked us because the 10-year warranty on a rental property is a serious asset — no landlord wants a call-out at 11pm in year 6.
The install
- Day 1 (morning): Isolated gas, water and electric. Drained the system. Removed the old Junior and controls.
- Day 1 (afternoon): Fitted the new Worcester Greenstar 4000. Re-piped the gas run to 22 mm (the old 15 mm was undersized). Fitted the MagnaClean and a new external filling loop.
- Day 2 (morning): Chemical hot flush across all 8 radiators using Fernox F3, followed by F1 inhibitor dosing. Commissioned to manufacturer spec, recorded the flue gas analysis, filled in the Benchmark log book.
- Day 2 (afternoon): Handover with tenants — walked them through the controls, left the manual, registered the 10-year warranty and CP12 with the Gas Safe Register.
What Chloe paid, all in
£2,150 fixed — that's the number that appeared on the quote and that's the number she paid. No supplementary charges for the gas re-pipe, no extra for the flush, no rate hikes because it took a day and a half instead of a day. See our 2026 Lancashire boiler replacement cost guide for typical figures.
Why BB2 matters
Blackburn BB2 has a lot of Victorian and 1930s terraced / semi stock with 15 mm gas runs — undersized for modern condensing boilers, which need 22 mm. A cheap quote that skips the re-pipe will fail commissioning (gas working pressure drops below 19 mbar at full rate) and either the engineer botches the sign-off or you get a warranty-void install. Ours never do.
Booking a new boiler in Blackburn or the surrounding BB1 / BB2 / BB3 postcodes? Start the instant boiler quote, or read our full Blackburn boiler installer page.
