Worcester boilers | We compare price, warranty & efficiency
How do Worcester Bosch boiler prices compare with Vaillant, Baxi and Ideal?
Worcester Bosch outsell every other boiler manufacturer in the UK but Vaillant, Ideal and Baxi are close seconds. We investigate Worcester boiler prices, warranty periods, efficiencies and heating outputs and compare against that of their nearest competitors. There are many other boiler manufacturers, many of which produce the same or better models for the same or less money. They are worth checking out in our comprehensive Guide to the best boilers.
Overview
Worcester Bosch win on efficiency
Worcesters tend to be the most efficient, but only the newer models.
Worcester Bosch are expensive
However their back up and warranty lengths are amongst the best.
Check out other great manufacturers
These four manufacturers offer some great boilers, but others do too. See our Guide to the best boilers.
OVERVIEW OF WORCESTER BOILERS
Worcester manufacture a wide range of combi, heat-only and system boilers for all sizes of property. The tables below separate Worcester boilers by type and run in size order.
Worcester Combi boilers
| Model | Cupboard fit | Boiler Price | Manufacturer Cover | Max Heating Output | Min Heating Output | Litres per minute hot water |
|---|---|---|---|---|---|---|
| Worcester Greenstar Compact 25Si | Y | £ 1,045 | 5-10 | 24kW | 8.1kW | 9.8 |
| Worcester Greenstar Compact 30Si | Y | £ 1,170 | 5-10 | 24kW | 7.0kW | 11.5 |
| Worcester Greenstar 2000 25 | N | £ 780 | 5-10 | 20kW | 4.8kW | 10 |
| Worcester Greenstar 2000 30 | N | £ 895 | 5-10 | 20kW | 4.8kW | 12 |
| Worcester Greenstar 8000 30 | N | £ 1,275 | 5-10 | 30kW | 3.0kW | 10.7 |
| Worcester Greenstar 8000 35 | N | £ 1,405 | 5-10 | 35kW | 3.5kW | 13.0 |
| Worcester Greenstar 8000 40 | N | £ 1,598 | 5-10 | 35kW | 3.5kW | 14.3 |
| Worcester Greenstar 8000 45 | N | £ 1,906 | 5-10 | 35kW | 3.5kW | 16.1 |
| Worcester Greenstar 8000 50 | N | £ 2,160 | 5-10 | 35kW | 3.5kW | 17.9 |
| Worcester Highflow 440CDi | N | £ 2,115 | 5-10 | 29kW | 7.4kW | 20.0 |
| Worcester Highflow 550CDi | N | £ 2,480 | 5-10 | 30kW | 9.7kW | 25.0 |
Worcester Heat only (Regular) boilers
| Model | Cupboard fit | Boiler Price | Manufacturer Cover | Max Heating Output | Min Heating Output | Litres per minute hot water |
|---|---|---|---|---|---|---|
| Worcester Bosch Greenstar 12Ri | Y | £ 810.00 | 5-10 | 12kW | 3.5kW | N/A |
| Worcester Bosch Greenstar 15Ri | Y | £ 830.00 | 5-10 | 15kW | N/A | |
| Worcester Bosch Greenstar 18Ri | Y | £ 885.00 | 5-10 | 18kW | 5.5kW | N/A |
| Worcester Bosch Greenstar 24Ri | Y | £ 940.00 | 5-10 | 24kW | 7.3kW | N/A |
| Worcester Bosch Greenstar 27Ri | Y | £ 1,045.00 | 5-10 | 27kW | 7.0kW | N/A |
| Worcester Bosch 8000 30 | N | £ 1,275.00 | 5-10 | 30kW | 3.0kW | N/A |
| Worcester Bosch 8000 35 | N | £ 1,510.00 | 5-10 | 35kW | 3.5kW | N/A |
| Worcester Bosch 8000 40 | N | £ 1,750.00 | 5-10 | 35kW | 3.5kW | N/A |
| Worcester Bosch 8000 45 | N | £ 2,000.00 | 5-10 | 35kW | 3.5kW | N/A |
| Worcester Bosch 8000 50 | N | £ 2,230.00 | 5-10 | 35kW | 3.5kW | N/A |
Worcester System boilers
| Model | Cupboard fit | Boiler Price | Manufacturer Cover | Max Heating Output | Min Heating Output | Litres per minute hot water |
|---|---|---|---|---|---|---|
| Worcester Bosch Greenstar System 12i | N | £ 900.00 | 5-10 | 12kW | 3.1kW | N/A |
| Worcester Bosch Greenstar System 15i | N | £ 950.00 | 5-10 | 15kW | 4.6kW | N/A |
| Worcester Bosch Greenstar System 18i | N | £ 1,050.00 | 5-10 | 18kW | 4.6kW | N/A |
| Worcester Bosch Greenstar System 24i | N | £ 1,060.00 | 5-10 | 24kW | 7.2kW | N/A |
| Worcester Bosch Greenstar System 27i | Y | £ 1,070.00 | 5-10 | 27kW | 7.0kW | N/A |
| Worcester Bosch Greenstar 8000 30 | N | £ 1,310.00 | 5-10 | 30kW | 3.0kW | N/A |
| Worcester Bosch Greenstar 8000 35 | N | £ 1,440.00 | 5-10 | 35kW | 3.5kW | N/A |
PRODUCT COMPARISON
How we judge the boilers - how low do they go?
We have compared models on 1) prices, 2) warranty period and 3) how low the boiler can go. The lowest minimum output is perhaps the most important feature of any boiler. The average UK requires just 6-8kW of heat on a very cold day and just 1kW-5kW the rest of the year.
For a boiler to operate efficiently all year round it must go down as low as possible. The lowest output boiler on the market in the UK is the Viessmann 200 at 1.9kW. The Worcester does well with the 8000 model as that goes down to 3.2kW and some of the other models come close. Although the 8000 is also one of the most expensive models.
Overview of our findings
We found that Worcester are great value in some categories and expensive for what they offered in others. Depending on the size and type of boiler you need, you may find that a Baxi, Vaillant or Ideal boiler actually gives a better package for the price compared to the Worcester boiler in that group. Whilst these four manufacturers make up the lion share of boiler sales in the UK, many other manufacturers have equal or sometimes better products on offer. Check out our Best boiler guide for more
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Combi boiler tables
Worcester combi boilers are presented here based on the number of bathrooms they would serve. All combi boilers are oversized for the heating systems they serve, which can make them very inefficient. It is important to pick a combi boiler that combi a good hot water output combined with a low minimum heating output. For more on the best boilers for this job, read our Guide to the best combi boilers.
1 bathroom properties - 9-10 litres per minute
The best of the smaller output boilers is the Worcester 8000 with a low output of 3.0kW, but it is the most expensive. The Worcester 2000 is also decent value offering a budget option boiler with 4.8kW minimum output, although the Ideal Independent offers the same performance for over £100 cheaper.
| Boiler Brand and Model | Cupboard fit | Boiler cost | Manufacturer Cover | Max Heating Output | Min Heating Output | Litres per minute hot water |
|---|---|---|---|---|---|---|
| Entry level | ||||||
| Ideal Independent C24 | Y | £ 670 | 5 | 24kW | 4.8kW | 9.9 |
| Budget | ||||||
| Baxi 400 424 | Y | £ 670 | 5 | 22kW | 5.2kW | 9.8 |
| Baxi Duotec 24 | N | 7 | 21kW | 7.4kW | 9.8 | |
| Worcester Greenstar 2000 25 | N | £ 780 | 5-10 | 20kW | 4.8kW | 10 |
| Ideal Logic + C24 | N | £ 825 | 7 | 24kW | 7.1kW | 9.9 |
| Mid range | ||||||
| Vaillant EcoFIT pure 825 | Y | £ 910 | 2-7 | 19kW | 5.3kW | 10.4 |
| Vailliant EcoTEC Pro 24 | N | £ 965 | 2-7 | 24kW | 9.6kW | 9.6 |
| Baxi Ecoblue Advance 24 | Y | £ 1,020 | 10 | 20kW | 4.9kW | 9.8 |
| Worcester Greenstar Compact 25Si | Y | £ 1,045 | 5-10 | 24kW | 8.1kW | 9.8 |
| Premium | ||||||
| Ideal Vogue C26 | N | £ 1,005 | 10 | 18kW | 4.0kW | 10.6 |
| Vaillant EcoTEC plus 825 | Y | £ 1,145 | 5-10 | 19kW | 3.8kW | 10.5 |
| Worcester Greenstar 8000 30 | N | £ 1,275 | 5-10 | 30kW | 3.0kW | 10.7 |
1 bathroom properties - 11-12 litres per minute
The Worcester 8000 is the best in class with a low minimum output of 3.0kW. The Baxi 400 has a slightly higher output but is great value at half the price of the 8000 model. The rest of the pack are cheaper but with quite high minimum outputs. For more efficient boilers use our Guide to the best combi boilers.
| Boiler Brand and Model | Cupboard fit | Boiler cost | Manufacturer Cover | Max Heating Output | Min Heating Output | Litres per minute hot water |
|---|---|---|---|---|---|---|
| Entry level | ||||||
| Ideal Independent C30 | Y | £ 745 | 5 | 24kW | 6.1kW | 12.3 |
| Baxi 400 428 | Y | £ 670 | 5 | 28kW | 5.2kW | 11.5 |
| Budget | ||||||
| Baxi Duotec 28 | Y | £ 885 | 7 | 24kW | 9.5kW | 11.5 |
| Ideal Logic+ C30 | Y | £ 890 | 7 | 24kW | 6.1kW | 12.4 |
| Worcester Greenstar 2000 30 | N | £ 895 | 5-10 | 20kW | 4.8kW | 12 |
| Mid range | ||||||
| Vaillant EcoTEC Pro 28 | N | £ 1,070 | 2-7 | 26kW | 9.6kW | 11.1 |
| Baxi Platinum 28 | N | £ 1,010 | 10 | 24kW | 9.5kW | 11.5 |
| Vailliant EcoFITpure 830 | Y | £ 1,110 | 2-7 | 26kW | 6.3kW | 12.4 |
| Vaillant EcoTEC Pro 30 | N | £ 1,115 | 2-7 | 25kW | 6.2kW | 12.3 |
| Baxi Ecoblue Advance 28 | Y | £ 1,170 | 10 | 25kW | 6.0kW | 11.5 |
| Worcester Greenstar Compact 30Si | Y | £ 1,170 | 5-10 | 24kW | 7.0kW | 11.5 |
| Premium | ||||||
| Worcester 8000 35 | N | £ 1,275 | 10 | 30kW | 3.5kW | 13.0 |
1-2 bathroom properties - 13-14 litres per minutes
Worcester recently released the 8000 model which combines great hot water performance with a low minimum output of 3.2kW. As such they are neck and neck with the Vaillant ecoTEC Green iQ. For other very efficient combi boilers, see our Guide to the best combi boilers
| Boiler Brand and Model | Cupboard fit | Boiler cost | Manufacturer Cover | Max Heating Output | Min Heating Output | Litres per minute hot water |
|---|---|---|---|---|---|---|
| Entry level | ||||||
| Entry level>Ideal Independent C35 | Y | £ 805 | 5 | 24kW | 7.1kW | 14.5 |
| Entry level>Budget | ||||||
| Entry level>Baxi Duotec 33 | N | £ 990 | 7 | 30kW | 10.2kW | 13.5 |
| Entry level>Mid range | ||||||
| Entry level>Ideal Logic+ C35 | Y | £ 1,035 | 7 | 24kW | 7.1kW | 14.5 |
| Entry level>Vailliant EcoFITpure 835 | Y | £ 1,098 | 2-7 | 25kW | 7.5kW | 14.4 |
| Entry level>Baxi Platinum 33 | N | £ 1,145 | 10 | 28kW | 10.2kW | 13.5 |
| Entry level>Baxi Ecoblue Advance 33 | Y | £ 1,300 | 10 | 28kW | 7.1kW | 13.5 |
| Entry level>Premium | ||||||
| Entry level>Vailliant EcoTEC plus 832 | N | £ 1,290 | 5-10 | 25kW | 7.2kW | 13.0 |
| Entry level>Ideal Vogue C32 | N | £ 1,115 | 10 | 26kW | 4.6kW | 13.1 |
| Entry level>Vailliant EcoTEC plus 835 | N | £ 1,470 | 5-10 | 30kW | 5.8kW | 14.3 |
| Entry level>Worcester Greenstar 8000 40 | N | £ 1,598 | 5-10 | 35kW | 3.5kW | 14.3 |
| Entry level>Vaillant EcoTEC Exclusive 835 with Green IQ | N | £ 1,651 | 5-10 | 24kW | 3.4kW | 14.5 |
2 bathroom properties - 15-16 litres per minutes
There is less to choose from as the boilers get bigger. The Worcester 8000 is worth raving about as it gives a high hot water performance with a low minimum output. The Ideal Vogue is also pretty decent for the price. For other brands of this quality check out our Guide to the best combi boilers.
| Boiler Brand and Model | Cupboard fit | Boiler cost | Manufacturer Cover | Max Heating Output | Min Heating Output | Litres per minute hot water |
|---|---|---|---|---|---|---|
| Budget | ||||||
| Baxi Duotec 40 | N | £ 1,045 | 7 | 34kW | 12.1kW | 16.4 |
| Mid range | ||||||
| Baxi Platinum 40 | N | £ 1,260 | 10 | 32kW | 12.1kW | 16.4 |
| Premium | ||||||
| Ideal Vogue C40 | N | £ 1,225 | 10 | 32kW | 5.7kW | 16.4 |
| Vailliant EcoTEC plus 838 | Y | £ 1,440 | 7-10 | 6.5kW | 15.9 | |
| Worcester Greenstar 8000 45 | N | £ 1,906 | 5-10 | 35kW | 16.4 |
2 + bathroom properties - 18-25 litres per minutes
Only Vaillant and Worcester manufacturer larger domestic sized boiler. The Vaillant ecoTEC Green iQ storage is by far the cheapest with a great minimum output of 4.3kW. The Worcester 8000 outperforms it but for a higher price.
| Boiler Brand and Model | Cupboard fit | Boiler cost | Manufacturer Cover | Max Heating Output | Min Heating Output | Litres per minute hot water |
|---|---|---|---|---|---|---|
| Mid range | ||||||
| Vaillant ecoTEC plus 938 storage combi | N | £ 1,610 | 5-10 | 30kW | 6.5kW | 20.0 |
| Premium | ||||||
| Vaillant ecoTEC Green iQ 843 | N | £ 1,700 | 5-10 | 33kW | 4.3kW | 17.8 |
| Worcester Highflow 440CDi | N | £ 2,115 | 5-10 | 29kW | 7.4kW | 20.0 |
| Worcester Highflow 550CDi | N | £ 2,480 | 5-10 | 30kW | 9.7kW | 25.0 |
| Worcester Greenstar 8000 50 | N | £ 2,160 | 5-10 | 35kW | 3.5kW | 17.9 |
Heat only boiler tables
Worcester regular boilers are presented here based on the rated output of the boiler. The average UK heat requirement is 6-8kW on a very cold day, however the smallest boilers available to buy are around 11-13kW. As such the smallest boilers will heat the majority of UK homes. The key consideration is the requirements of the hot water tank. Some small tanks will only require 12kW of heat from the boiler whilst larger tanks serving multiple bathrooms will need perhaps 25kW and upwards. We have grouped boilers together based on hot water requirements - your attending heating engineer will be able to guide you.
1-3 BEDROOM HOMES, SMALL HOT WATER CYLINDERS
Both the Worcester Ri and 8000 models offer low minimum outputs and no-one else really comes close. At 3.4kW, the Ri is a good all round purchase.
| Boiler brand and model | Cupboard fit | Boiler cost | Manufacturer Cover | Warranty or Guarantee | Max Heating Output | Min Heating Output |
|---|---|---|---|---|---|---|
| Budget | ||||||
| Baxi 200 Heat 12 | Y | £ 600.00 | 3 | W | 13kW | 7.5kW |
| Baxi 400 Heat 12 | Y | £ 654.00 | 5 | W | 13kW | 7.5kW |
| Ideal Logic Heat 12 | Y | £ 695.00 | 2 | W | 12kW | 5.1kW |
| Mid range | ||||||
| Vaillant ecoFIT pure regular 12 | Y | £ 740.00 | 2-7 | G | 12kW | 4.5kW |
| Vaillant ecoTEC plus regular 12 | Y | £ 805.00 | G | 12kW | 4.5kW | |
| Ideal Logic + Heat 12 | Y | £ 705.00 | 7 | W | 12kW | 5.1kW |
| Worcester Bosch Greenstar 12Ri | Y | £ 810.00 | 5-10 | G | 12kW | 3.4kW |
| Premium | ||||||
| Worcester Greenstar 8000 30 | N | £ 1,275 | 5-10 | G | 30kW | 3.0kW |
2-5 BEDROOM HOMES, LARGER HOT WATER CYLINDER
Again both the Worcester models provide the best efficiencies all year around. But note, the minimum output jumps from 3.4kW on the 12Ri to 4.6kW on the 15Ri. Make absolutely sure you need 15kW at peak times as it won't as efficient if you don't (unless you need it for stored hot water). Both Vaillant models are comparable with the Ri in this group, but the 8000 is the best performing, although the most expensive.
| Boiler brand and model | Cupboard fit | Boiler cost | Manufacturer Cover | Warranty or Guarantee | Max Heating Output | Min Heating Output |
|---|---|---|---|---|---|---|
| Budget | ||||||
| Baxi 200 Heat 15 | Y | £ 630.00 | 3 | W | 16kW | 7.5kW |
| Baxi 400 Heat 15 | Y | £ 685.00 | 5 | W | 16kW | 7.5kW |
| Ideal Logic Heat 15 | Y | £ 720.00 | 2 | W | 15kW | 5.1kW |
| Mid range | ||||||
| Vaillant ecoFIT pure regular 15 | Y | £ 775.00 | 2-7 | G | 15kW | 4.5kW |
| Ideal Logic + Heat 15 | Y | £ 740.00 | 7 | W | 15kW | 5.1kW |
| Worcester Bosch Greenstar 15Ri | Y | £ 830.00 | 8 | G | 15kW | 4.6kW |
| Vaillant ecoTEC plus regular 15 | Y | £ 880.00 | 5-10 | G | 15kW | 4.5kW |
| Premium | ||||||
| Worcester Greenstar 8000 30 | N | £ 1,275 | 5-10 | G | 30kW |
3.0kW |
3-5 BEDROOM HOMES, MULTIPLE BATHROOMS
The Worcester 8000 outperforms everything in this group by some margin. The other models demonstrate very well how the minimum output increases as the maximum output increase. Be absolutely sure you need an 18kW boiler. We talk more about the perils of oversizing in our blog: Why oversized boilers are bad for your budget and the planet.
| Boiler brand and model | Cupboard fit | Boiler cost | Manufacturer Cover | Warranty or Guarantee | Max Heating Output | Min Heating Output |
|---|---|---|---|---|---|---|
| Budget | ||||||
| Baxi 200 Heat 18 | Y | £ 690.00 | 3 | W | 19kW | 7.5kW |
| Baxi 400 Heat 18 | Y | £ 715.00 | 5 | W | 19kW | 7.5kW |
| Baxi 200 Heat 21 | Y | £ 749.00 | 3 | W | 89% | 21 |
| Ideal Logic Heat 18 | Y | £ 770.00 | 2 | W | 18kW | 5.1kW |
| Mid range | ||||||
| Vaillant ecoFIT pure regular 18 | Y | £ 845.00 | 2-7 | G | 18kW | 5kW |
| Ideal Logic+ Heat 18 | Y | £ 780.00 | 7 | W | 18kW | 5.1kW |
| Worcester Bosch Greenstar 18Ri | Y | £ 885.00 | 5-10 | G | 18kW | 5.5kW |
| Vaillant ecoTEC plus regular 18 | Y | £ 965.00 | 5-10 | W | 18kW | 5kW |
3-5 BEDROOM HOMES, MULTIPLE BATHROOMS + VERY LARGER HOT WATER CYLINDER
Again the Worcester 8000 outperforms everything in this group, only the Ideal models come close with low minimum outputs of 5.1kW. Be absolutely sure you need a 24kW boiler. We talk more about the perils of oversizing in our blog: Why oversized boilers are bad for your budget and the planet.
For other big output boilers with low minimum outputs, see our Guide to the best boilers
| Boiler brand and model | Cupboard fit | Boiler cost | Manufacturer Cover | Warranty or Guarantee | Max Heating Output | Min Heating Output |
|---|---|---|---|---|---|---|
| Budget | ||||||
| Baxi 200 Heat 24 | Y | £ 755.00 | 3 | W | 25kW | 7.5kW |
| Baxi 400 Heat 24 | Y | £ 780.00 | 5 | W | 25kW | 7.5kW |
| Ideal Logic Heat 24 | Y | £ 805.00 | W | 24kW | 5.1kW | |
| Ideal Logic + Heat 24 | Y | £ 880.00 | 7 | W | 24kW | 5.1kW |
| Mid range | ||||||
| Vaillant ecoFIT pure regular 25 | Y | £ 935.00 | 2-7 | G | 25kW | 6.1kW |
| Worcester Bosch Greenstar 24Ri | Y | £ 940.00 | 5-10 | G | 24kW | 7.3kW |
| Vaillant ecoTEC plus regular 24 | Y | £ 1,035.00 | 5-10 | G | 24kW | 6.1kW |
| Worcester Bosch Greenstar 27Ri | Y | £ 1,045.00 | 5-10 | G | 27kW | 7.0kW |
| Premium | ||||||
| Worcester Greenstar 8000 30 | N | £ 1,275 | 5-10 | G | 30kW | 3.0kW |
PRIORITY DOMESTIC HOT WATER SYSTEMS
You are unlikely to ever need a boiler of this size for heating, however some very large homes with big hot water requirements may need 30kW boiler for hot water. Boilers of this size are used however for Priority Domestic Hot Water systems. The Worcester 8000 outperforms everything in this group. For other big output boilers with low minimum outputs, see our Guide to the best boilers.
| Boiler brand and model | Cupboard fit | Boiler cost | Manufacturer Cover | Warranty or Guarantee | Max Heating Output | Min Heating Output |
|---|---|---|---|---|---|---|
| Budget | ||||||
| Baxi 400 Heat 30 | Y | £ 850.00 | 5 | W | 30kW | 7.5kW |
| Ideal Logic Heat 30 | Y | £ 910.00 | 2 | W | 30kW | 6.4kW |
| Mid range | ||||||
| Vaillant ecoFIT pure regular 30 | Y | £ 975.00 | 2-7 | G | 30kW | 7.5kW |
| Ideal Logic+ Heat 30 | Y | £ 925.00 | 7 | W | 30kW | 6.4kW |
| Vaillant ecoTEC plus regular 30 | Y | £ 1,095.00 | 5-10 | G | 30kW | 7.5kW |
| Worcester Bosch Greenstar 30Ri | Y | £ 1,085.00 | 5-10 | G | 30kW | 7.0kW |
| Premium | ||||||
| Worcester Greenstar 8000 30 | N | £ 1,275 | 5-10 | G | 30kW | 3.0kW |
System boiler tables
Worcester system boilers are presented here based on the typical size property they would serve. Find your property size and then compare the appropriate Worcester boiler with other popular manufacturers.
1-3 BEDROOM HOMES, SMALL HOT WATER CYLINDER
Ignore that the Worcester boiler is a 30kW output, the important figure is the lowest minimum output of 3kW. The lower the boiler can go, the more efficient it can run all year around. Worcester is however the most expensive.
| Boiler brand and model | Cupboard fit | Boiler cost | Manufacturer Cover | Warranty or Guarantee | Max Heating Output | Min Heating Output |
|---|---|---|---|---|---|---|
| Mid range | ||||||
| Vaillant ecoTEC plus system 612 | N | £ 910 | 5-10 | G | 12kW | 3.3kW |
| Vaillant ecoFIT pure system 612 | Y | £ 865 | 2-7 | G | 12kW | 4.7kW |
| Worcester Bosch Greenstar System 12i | N | £ 900 | 5-10 | G | 12kW | 3.1kW |
| Worcester Bosch Greenstar 8000 30 | N | £1,310 | 5-10 | G | 30kW | 3.0kW |
2-5 BEDROOM HOMES, LARGER HOT WATER CYLINDER
The Ideal Vogue and Vaillant ecoTEC offer great packages. Low minimum output for over £400 less than the Worcester 8000.
| Boiler brand and model | Cupboard fit | Boiler cost | Manufacturer Cover | Warranty or Guarantee | Max Heating Output | Min Heating Output |
|---|---|---|---|---|---|---|
| Entry level | ||||||
| Ideal Logic System 15 | Y | £ 765 | 2 | W | 15kW | 5.1kW |
| Mid range | ||||||
| Ideal Logic + System 15 | Y | £ 795 | 7 | W | 15kW | 5.1kW |
| Vaillant ecoTEC plus system 15 | N | £ 960 | 5-10 | G | 15kW | 3.3kW |
| Vaillant ecoFIT pure system 15 | Y | £ 925 | 2-7 | G | 15kW | 4.7kW |
| Worcester Bosch Greenstar System 15i | N | £ 950 | 5-10 | G | 15kW | 4.6kW |
| Premium | ||||||
| Ideal Vogue System S15 | N | £ 905 | 10 | W | 15kW | 3.2kW |
| Worcester Bosch Greenstar 8000 30 | N | £1,310 | 5-10 | G | 30kW | 3.0kW |
3-5 BEDROOM HOMES, MULTIPLE BATHROOMS
You can see that the lower minimum output starts to increase with a lot of the larger models, so be absolutely sure you need an 18kW boiler! Oversizing boiler is every inefficient, only get an 18kW boiler if you need it for hot water production. For more see our guide: Why oversized boilers are bad for your bank balance and the planet.
| Boiler brand and model | Cupboard fit | Boiler cost | Manufacturer Cover | Warranty or Guarantee | Max Heating Output | Min Heating Output |
|---|---|---|---|---|---|---|
| Entry level | ||||||
| Ideal Logic System 18 | Y | £ 805 | 2 | W | 18kW | 5.1kW |
| Mid range | ||||||
| Ideal Logic + System 18 | Y | £ 895 | 7 | W | 18kW | 5.1kW |
| Vaillant ecoFIT pure system 618 | Y | £1,000 | 2-7 | G | 18kW | 5.2kW |
| Vaillant ecoTEC plus system 618 | Y | £1,080 | 5-10 | G | 18kW | 4.1kW |
| Baxi System 618 | Y | £ 975 | 7 | W | 20kW | 4.9kW |
| Worcester Bosch Greenstar System 18i | N | £1,050 | 5-10 | G | 18kW | 4.6kW |
| Premium | ||||||
| Ideal Vogue System S18 | N | £ 985 | 10 | W | 18kW | 3.9kW |
| Worcester Bosch Greenstar 8000 30 | N | £1,310 | 5-10 | G | 30kW | 3.0kW |
3-5 BEDROOM HOMES, MULTIPLE BATHROOMS + VERY LARGE HOT WATER CYLINDER
Only the Worcester stays really efficient with a low minimum output of 3kW, although arguably for a house this size the lowest heat requirement might be over this anyway. The Ideal Logic is a great budget model. Be sure you need 24kW - the only way to know if to have a heat loss calculation carried out. For more see our guide: Why oversized boilers are bad for your bank balance and the planet.
| Boiler brand and model | Cupboard fit | Boiler cost | Manufacturer Cover | Warranty or Guarantee | Max Heating Output | Min Heating Output |
|---|---|---|---|---|---|---|
| Entry level | ||||||
| Ideal Logic System 24 | Y | £ 850 | 2 | W | 24kW | 5.1kW |
| Mid range | ||||||
| Worcester Bosch Greenstar System 24i | N | £ 1,060 | 5-10 | G | 24kW | 7.2kW |
| Worcester Bosch Greenstar System 27i | Y | £ 1,070 | 5-10 | G | 24kW | 7.0kW |
| Baxi System 624 | Y | £ 1,085 | 7 | W | 25kW | 4.9kW |
| Vaillant ecoFIT pure system 625 | Y | £ 1,150 | 2-7 | G | 25kW | 6.4kW |
| Vaillant ecoTEC plus system 624 | N | £ 1,225 | 5-10 | G | 24kW | 5.7kW |
| Premium | ||||||
| Ideal Vogue System S26 | N | £ 1,110 | 10 | W | 26kW | 5.6kW |
| Vaillant ecoTEC exclusive 27 | N | £ 1,345 | 5-10 | G | 27kW | 4.2kW |
| Worcester Bosch Greenstar 8000 30 | N | £1,310 | 5-10 | G | 30kW | 3.0kW |
3-5 BEDROOM HOMES, MULTIPLE BATHROOMS + VERY LARGE HOT WATER CYLINDER
On the basis that the average room needs 1kW of heat, some of these boilers could heat a 30 room house. The only way to know is to commission a heat loss calculation. However if you have a large demand for hot water you may need a larger boiler. All of the lowest minimum outputs have increased with the exception of the Worcester 8000 but that may not be a problem if you really need 30kW on a cold day.
| Boiler brand and model | Cupboard fit | Boiler cost | Manufacturer Cover | Warranty or Guarantee | Max Heating Output | Min Heating Output |
|---|---|---|---|---|---|---|
| Budget | ||||||
| Ideal Logic System 30 | Y | £ 885 | 2 | W | 30kW | 6.4kW |
| Mid range | ||||||
| Ideal Logic + System 30 | Y | £ 895 | 7 | W | 30kW | 6.4kW |
| Worcester Bosch Greenstar System 30i | Y | £1,112 | 5-10 | G | 30kW | 7.0kW |
| Vaillant ecoTEC plus system 630 | N | £1,310 | 5-10 | G | 30kW | 6.4kW |
| Vaillant ecoFIT pure system 630 | Y | £ 1,215 | 2-7 | G | 30kW | 7.5kW |
| Premium | ||||||
| Ideal Vogue System S32 | N | £ 1,190 | 10 | W | 32kW | 6.8kW |
| Worcester Bosch Greenstar 8000 30 | N | £1,310 | 5-10 | G | 30kW | 3.0kW |
PRIORITY DOMESTIC HOT WATER SYSTEMS
These boilers are capable of heating enormous homes and should only be specified following a heat loss calculation. You may need a larger boiler for hot water production particularly if your engineer is using a priority domestic hot water systems.
| Boiler brand and model | Cupboard fit | Boiler cost | Manufacturer Cover | Warranty or Guarantee | Max Heating Output | Min Heating Output |
|---|---|---|---|---|---|---|
| Mid range | ||||||
| Vaillant ecoTEC plus system 37 | N | £1,440 | 5-10 | G | 37kW | 7.1kW |
| Premium | ||||||
| Worcester Bosch Greenstar 8000 35 | N | £1,450 | 5-10 | G | 35kW | 5.5kW |
Overview of boiler types
Combi boilers
A combination boiler is a single unit that provides heating and hot water to the home. In it provides instantaneous hot water direct from the cold mains. This is different from a traditional system which stores hot water in a tank in advance of use, i.e. a hot water cylinder is not required. Combi boilers are great for freeing up space but do not work well when water pressure is poor.
Heat only (regular) boilers
A regular boiler provides heating directly to the radiators and works with a hot water cylinder to provide hot water. These are usually open-vented heating systems (they can be sealed), i.e. there is a Feed and Expansion tank in the loft. A direct replacement of a regular boiler is very cost effective, however it does limit the new boiler warranty to cover the heating only. The other components of the system, such as pumps, valves and the hot water cylinder are not covered and will be subject to on going maintenance and replacement liability.
System boilers
Like regular boilers, system boilers work with a hot water cylinder. Unlike regular boilers, the system is not open-vented, i.e. there are no tanks in the loft. In addition, all of the components that would normally be outside a regular boiler (pumps, valves etc) are integrated into the boiler. These are a modern version of the regular boiler and are often installed along side unvented hot water cylinders. They are great for larger properties with more than one bathroom, but only if the water pressure is good.
