Goodbye 440CDi & 550CDi – Hello Worcester Greenstar 8000 F Floor Standing Combi
Worcester Bosch is phasing out the iconic Greenstar Highflow 440CDi and 550CDi floor-standing combi boilers in natural gas and LPG. Here’s what that means for your next boiler install – and why the new Greenstar 8000 F 35kW & 50kW floor-standing combi range is the natural successor.
What’s changing – in plain English
For years, the Worcester Greenstar Highflow 440CDi and 550CDi have been the go-to floor-standing combi boilers for bigger UK homes that needed strong hot water performance without a separate cylinder. They offered high flow rates and the convenience of a combi, all from a unit that could sit under a kitchen worktop.
Worcester Bosch has now discontinued the CDi combi range, including the Highflow floor-standing models, and is focusing on newer, higher-efficiency boiler families. For floor-standing combis, that means the spotlight is now on the Greenstar 8000 F 35kW and 50kW combi boilers in both natural gas (NG) and LPG.
Who needs to care about the 440CDi / 550CDi discontinuation?
You should pay attention to this change if:
- You currently have a Worcester Greenstar Highflow 440CDi or 550CDi floor-standing combi.
- You’re planning a boiler upgrade in a large property (multiple bathrooms, high hot water demand).
- You’re an installer who regularly fits or services the Highflow range.
- You’re working on a new-build or renovation where a floor-standing combi in NG or LPG is required.
In all of these scenarios, the new Greenstar 8000 F floor-standing combi range is what you should be looking at next.
440CDi & 550CDi vs Greenstar 8000 F – quick comparison
Greenstar Highflow 440CDi & 550CDi (NG & LPG)
- Floor-standing combi boilers for large homes.
- High domestic hot water (DHW) flow rates around 20+ L/min (at typical temperature rises).
- Could sit under a standard kitchen worktop.
- Reliable, well-known “workhorse” models now discontinued.
Greenstar 8000 F 35kW & 50kW Combi (NG & LPG)
- Modern floor-standing combi with outputs up to 50kW.
- Available in both natural gas and LPG variants.
- Designed to fit under a kitchen counter (approx. 850×600×600mm footprint).
- Intuitive touch controls, A-rated hot water efficiency and improved DHW performance.
- SimpleSwitch concept to make swaps from CDi Highflow / FS CDi easier for installers.
At-a-glance feature table
| Model | Typical application | Key points |
|---|---|---|
| Greenstar Highflow 440CDi | 3–4 bedroom home, 1–2 bathrooms |
|
| Greenstar Highflow 550CDi | Larger homes with higher hot water demand |
|
| Greenstar 8000 F 35kW Combi (NG / LPG) | Replacement for many 440CDi-type installs |
|
| Greenstar 8000 F 50kW Combi (NG / LPG) | Replacement for many 550CDi-type installs |
|
Natural gas & LPG options – still covered
One of the reasons the 440CDi and 550CDi Highflow models were so popular is that they were available in both NG and LPG, making them ideal for off-grid properties as well as mains gas homes.
The good news is that the Greenstar 8000 F combi continues this flexibility, with:
- Greenstar 8000 F 35kW Combi NG and 35kW Combi LPG.
- Greenstar 8000 F 50kW Combi NG and 50kW Combi LPG.
That means whether you’re on mains gas in Reading or off-grid on LPG in rural Berkshire, you can stay with a trusted floor-standing Worcester Bosch combi platform.
Why installers will like the Greenstar 8000 F
Worcester has clearly designed the Greenstar 8000 F range with straightforward swaps in mind. A few installer-friendly highlights:
- SimpleSwitch concept – makes it easier to replace existing Highflow / FS CDi boilers with minimal re-pipe work.
- Floor-standing, under-counter footprint – fits neatly in kitchens, utility rooms and plant cupboards.
- Improved DHW efficiency – better hot water performance compared with previous generations.
- Easy access for servicing – designed with front access and logical component layout.
- Optional system filter inside the case (combi only) – keeps installs tidy and protected.
At GetPlumb, we can supply full 8000 F packs – including boiler, flue kit, filter, controls and chemicals – so you can price jobs quickly and competitively.
Typical upgrade paths we expect to see
If you currently have a 440CDi Highflow
In many cases, a Greenstar 8000 F 35kW combi will be the natural successor – offering similar or improved hot water performance with a more modern and efficient design.
However, if you’ve extended the property (extra bathroom, loft conversion, garden room etc.), you might now be better suited to the 50kW combi. Always get your installer to do a quick heat loss check and review your hot water usage.
If you currently have a 550CDi Highflow
If your 550CDi was originally specified to cope with very high DHW demand – multiple showers in use, big family, or high-end fittings – the Greenstar 8000 F 50kW combi is likely to be the first model to consider.
Where demand has reduced (for example, fewer occupants now) a 35kW may also be possible, but the decision should only be made after a proper survey.
Important: These are starting points only, not final specifications. Always confirm the correct boiler size with a qualified Gas Safe engineer.
FAQs – 440CDi / 550CDi and the new 8000 F range
Why order your Greenstar 8000 F from GetPlumb?
- Independent merchant with Worcester expertise – we speak boilers all day, every day.
- Trade-friendly pricing and quick quotes for installers and developers.
- Stock of flues, filters, controls and chemicals to complete the job in one go.
- Local delivery around Reading, Slough and surrounding areas, plus nationwide courier options.
- Friendly team on the phone if you need to double-check sizing or compatibility.