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Worcester Bosch Greenstar 25Si & 30Si Boilers

Worcester Bosch Greenstar Si Boilers are part of Worcester’s mid-range appliances. It has two heating outputs, and is ideal for apartments and smaller properties. Average prices start from around £725 excluding VAT and installation costs.

This small yet powerful combi boiler is SEDBUK A rated with 90.1% Natural Gas and 91.9% LPG fuel efficiency. Its compact and lightweight design comes with compressed hydraulics and multi-directional fluing for reliability and simple installation. Plus hot water and central heating temperatures can be controlled effortlessly with Worcester’s keep- hot facility, which means instant hot water is always on tap.

Worcester Bosch Greenstar Si boilers are also compatible with a wide range of Worcester controls, including simple-to-operate mechanical timers, sophisticated digital programmers, room thermostats and new generation intelligent controls. The use of these effective controls will improve the overall performance of a heating system by significantly reducing fuel consumption and energy bills.

Worcester Bosch Greenstar Si Boilers Overview

ModelTypeDimensionsMaximum Flow RateOutputEfficiency RatingTypical Price
Greenstar 25SiCombiH – 710 mm
W – 400 mm
D – 330 mm
10.2 l/min25 kWA 90% and above£851.9
Greenstar 30SiCombiH – 710 mm
W – 400 mm
D – 330 mm
12.3 l/min30 kWA 90% and above£952.64
Key Features & Benefits
SEDBUK Band AHigh energy efficiency
NOx Class 5- Low NOx and CO2 emissionsEnvironmentally friendly
With DHW control and fault finding diagnosticsUser comfort Energy efficiency Boiler reliability Economy
Compatible with DT20 twin channel digital programmer, DT20RF digital RF thermostat, DT10RF digistat & optimiser.User comfort Energy efficiency Boiler reliability Economy
Compatible with simple mechanical controls MT10 & MT10RFBoiler reliability
Compatible with Bosch Intelligent controls like FR10 intelligent room thermostat, FR110 programmable room thermostat and FW100 weather compensation controller.Boiler reliability
Keep hot facility for instantly available hot waterConvenience
Multi-directional fluingSiting flexibility
Compact dimensionsSiting flexibility
Metal wall mounting frame hides pipework from viewSiting flexibility
Inbuilt frost protectionLonger boiler lifespan
Worcester- Bosch brand reliabilityPeace of mind
2 or 5 year Warranty until 30th June 2013 (terms & conditions apply) and 10 year guarantee on primary heat exchanger.Peace of mind

What we think of the Worcester Greenstar Si

Just two models make up this range of boilers, the first rated at 25kW and the other at 30kW. The former provides hot water at a rate of just over ten litres a minute, whereas the latter has the slightly faster rate of 12.3 litres a minute. Both models can work on either natural gas, or LPG.

The main benefits of the Combi Si – which means you don’t have to be burdened with finding a home for a hot water storage tank, or a cold water cistern – is the size. It’s power ratings means that it is suitable for a flat, or a small house.

At a wee bit over 30kg and with slim proportions, this is a boiler which can be neatly fitted into a small kitchen space. It is especially good for cupboards and given its neat controls, it is a useful worker which provides good heat.

Getting a Competitive Boiler Quote

We suggest you do your research before purchasing your new Greenstar Si Combi boiler as prices can vary. Get a few quotes from local boiler installers and one from a national installer to find the best boiler price for your budget and requirements.

Making sure your engineer is Gas Safe Registered is essential to ensure the work is done thoroughly and safely.

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1 review for Worcester Bosch Greenstar 25Si & 30Si Boilers

What Customers Are Saying

Rated 5 out of 5
20 February 2014

No Title

Needed a new boiler, the existing one being 11 yrs old and was letting us down.
We got the Worcester Greenstar si – excellent performance. Without a doubt our gas bill has dropped and also B/Gas have dropped our monthly payment by £5. Installed at the same time by B/Gas were remote Smart Meters for both the gas and the electric – so everything is bang up to date
B/Gas installed, did an excellent job – they charge too much for sure but we were in a poor position at that time and needed the job done asap. But, hey ho, all good now and the house up for sale with a new boiler can only be a plus point.
I would heartily recommend the Worcester boiler – and B/Gas for fitting but not for their charge.

M Lacey