Worcester Bosch Boiler & Heat Pump Installation in Cornwall

The Greenstar 4000 launched in 2021 as Worcester's volume A-rated boiler, replacing the older Greenstar i. It's available in combi (25/30kW), system (12/15/18/24/30kW) and regular (12/15/18/24/30kW) variants, all with stainless steel heat exchangers and ErP A-rated efficiencies of 94% gross. The 4000 is the right answer for most Cornish three- and four-bedroom homes where the priority is reliable, well-supported heat at a competitive price point. CCS as a Worcester Accredited Installer can offer up to 10 years parts and labour warranty on the Greenstar 4000 range, which is exceptional for the price.

The 4000's compact 600mm height fits standard kitchen unit cupboards — useful for Cornish flats and apartments where boiler location is constrained. The internal Wave wireless thermostat option provides simple weather compensation control without requiring a smart home system.

The Greenstar 8000 Lifestyle is Worcester's flagship gas boiler, offering up to 12 years parts and labour warranty (industry-leading), the highest ErP A-rated efficiency band, and Cornwall-relevant features like the larger heat exchanger that better tolerates the slightly variable mains pressure common at the end of long Cornish supply runs. Available in combi (30/35/40/45/50kW), system and regular configurations, the 8000 Lifestyle is our default recommendation for premium customers and larger properties.

For homes with high simultaneous hot water demand (multiple bathrooms in use at once), the 8000 Lifestyle Combi 50kW delivers 20.4 litres per minute at 35°C rise — more than enough for a busy family home. The boiler's load-modulation ratio of 1:10 means it can throttle right down to 5kW for gentle heating runs in mild Cornish weather, avoiding the inefficient cycling that plagues over-sized fixed-output boilers.

The Compress 7000i AW launched in 2024 as Worcester's first R290 propane monobloc heat pump, available in 5kW, 7kW and 9kW outputs. It's MCS-certified, qualifies for the £7,500 BUS grant, and benefits from Worcester's UK-based technical support and Worcester Bosch Group's Bosch parent's deep heat pump engineering pedigree. SCOP figures of 4.85 at 35°C and 3.55 at 55°C put the 7000i AW competitive with Vaillant aroTHERM plus and Daikin Altherma 3.

What sets the 7000i AW apart for Cornish customers is the integrated Worcester service network — the same Gas Safe and renewables engineers who already service Worcester boilers across Cornwall now cover heat pumps too. For homeowners doing a phased boiler-to-heat-pump transition over several years, staying within the Worcester ecosystem simplifies servicing, parts and warranty.

Around 35% of Cornish properties are off the mains gas grid — particularly in West Penwith, the Lizard, Bodmin Moor and rural North Cornwall. Many still rely on oil-fired heating. While CCS actively encourages off-grid customers to consider heat pumps (and the BUS grant is specifically targeted at oil-to-heat-pump conversions), we recognise that for some properties — listed buildings with high heat loss, holiday lets needing fast heat-up, properties with severe grid constraints — a high-efficiency oil boiler remains the pragmatic short-term choice.

The Greenstar Heatslave II achieves 92% net efficiency and is available in 12/18/25/32kW outputs. Worcester offers up to 10 years warranty when installed by an OFTEC-registered Worcester Accredited Installer like CCS. We supply, fit and commission across all Cornish off-grid postcodes.

Worcester Bosch's national service network is the largest of any heating manufacturer, with engineers in Cornwall providing same-or-next-day warranty response. For our installed customers, CCS handles all warranty claims directly with Worcester, removing the homeowner from the administrative burden. We also offer fixed-price service contracts (£140/year for combi gas boilers, £180/year for oil and heat pump) that maintain warranty validity and include annual flue gas analysis, condensate trap inspection, and water quality test.

Typical fully installed pricing (May 2026):

• Greenstar 4000 Combi 30kW — from £2,650
• Greenstar 8000 Lifestyle Combi 35kW — from £3,450
• Greenstar 8000 Lifestyle System 18kW — from £3,200
• Greenstar Heatslave II Oil 25kW — from £3,800
• Compress 7000i AW 7kW + 200L cylinder — from £13,400 (before BUS grant)
• Compress 7000i AW 9kW + 250L cylinder — from £15,200 (before BUS grant)

Boiler prices include flue, filter, system flush, Building Regulations notification and Worcester warranty registration. Heat pump prices include 0% VAT and qualify for the £7,500 BUS grant — so a 7kW Compress 7000i AW costs from £5,900 net of grant. See finance options spreading payments over 24, 60 or 120 months.