Combi Boiler Install in Brentwood

The Brief

A family home in Brentwood was running a 14-year-old conventional boiler with a hot water cylinder and a loft tank. Pressure was holding fine, but the unit was clearly past its efficient life and the airing cupboard was prime usable storage for the household. They asked us for a quote on a like-for-modern conversion: combi boiler in the kitchen, cylinder out, loft tank decommissioned, with the family back on hot water before the kids' bath time.

What We Did

The job was scoped, quoted and delivered across two working days:

• Day one, isolation and strip-out: Drained down the system, isolated gas and water, removed the conventional boiler, hot water cylinder and loft tank. Loft cleared and capped, airing cupboard freed up.
• New Worcester Bosch Greenstar 8000 Style 30 kW combi: Sized against the property's radiator count and shower count. Hung in the original boiler position to keep the flue route clean.
• Refreshed the connections: New cold inlet, isolation valves, drain points and pressure relief routing. Every joint pressure-tested before refilling.
• Magnetic filter fitted: Magnaclean Pro2 on the return, to catch iron oxide before it reaches the new heat exchanger.
• Full system flush: Sentinel chemical flush across every radiator, then dosed with Sentinel X100 inhibitor. Cold spots gone, every radiator hot top-to-bottom.
• Day two, commissioning and handover: Brought up to pressure, balanced the system, set the heating curve, ran combustion analysis with a flue gas analyser, and walked the family through the controls.
• Warranty registered: Worcester Bosch 10-year manufacturer warranty submitted on the day so the cover was active before we left.

The Result

Hot water back on by 4pm on day two, exactly as quoted. Combustion analysis put the new combi at 95% efficiency, compared to roughly 72% on the old conventional unit before removal. The household has gained the airing cupboard back as actual storage, freed up the loft from the cold-water tank, and cut the gas bill in measurable terms across the first winter.

More importantly, the family has stepped from a 'when will it fail' anxiety into a fit-and-forget system for the next decade. The 10-year warranty is registered, the magnetic filter and inhibitor are protecting the new heat exchanger, and we've put a yearly service reminder in the diary so the warranty stays valid.

Job Duration: Two working days from drain-down to commissioning, including the system flush, warranty registration and tank decommission.

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