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Great Home

Independent Advice On Improving Your Home

Gas System Boilers

Gas system boilers, like heat only boilers, provide heat to radiators and stored hot water cylinders. System boilers are used for both high pressure unvented systems as well as gravity fed systems (with a cold water tank in the loft). System boilers differ from heat only boilers in that they have additional components, such as a water pump, built into the unit rather than being provided separately. As a result they tend to be slightly higher in price but on new installations this is more than offset by ease of installation and not having to buy additional components.

Below we list the popular system boiler options by power output in kW and then brand. Note that the prices are for the boiler only and do not include the flue. They are also typical prices and do not reflect any price promotions with a specific plumbers merchant or retailer. On occasions, manufacturers offer promotional packages which include the flue.

See also prices for: Heat Only Boilers and Combi Boilers.

If you want an indication of what you may pay for a boiler replacement including installation then use our replacement boiler cost online calculator. You can then compare any quotations from installers with this guideline estimate.

Power
Output
ProductTypical price
inc VAT
Warranty
Period
Years *
Technical
Details
9kWWorcester Bosch Greenstar 9i System£971.605View
12kWGlow-worm Energy 12kW system£795.917View
12kWPotterton Promax 12 plus system £814.591View
12kWVaillant ecoFIT pure 612 system£881.232View
12kWVaillant ecoTEC plus 612 system£936.445View
12kWWorcester Bosch Greenstar 12i System£936.105View
15kWBaxi Megaflo System 15£900.797View
15kWGlow-worm Energy 15kW system£816.347View
15kWIdeal Vogue Gen2 System S15£996.368View
15kWIdeal Vogue Max System 15£993.6510View
15kWIdeal Logic Max System S15£965.6110View
15kWIdeal Logic+ Plus System S15£857.917View
15kWPotterton Promax 15 plus system £829.101View
15kWVaillant ecoFIT pure 615 system£943.732View
15kWVaillant ecoTEC plus 615 system£997.915View
15kWWorcester Bosch Greenstar 15i System£987.165View
18kWBaxi Megaflo System 18£929.297View
18kWGlow-worm Energy 18kW system£851.217View
18kWIdeal Logic Max System S18£1,037.5010View
18kWIdeal Vogue Max System 18£1,070.8310View
18kWIdeal Logic+ Plus System S18£898.317View
18kWIdeal Vogue Gen2 System S18£1,077.368View
18kWPotterton Gold 18 System£613.182View
18kWPotterton Promax 18 plus system £846.631View
18kWVaillant ecoTEC plus 618 system£1,103.105View
18kWVaillant ecoFIT pure 618 system£1,019.792View
18kWWorcester Bosch Greenstar 18i System£1,046.635View
21kWWorcester Bosch Greenstar 21i System£1,094.945View
24kWBaxi Megaflo System 24£1,019.347View
24kWIdeal Logic+ Plus System S24£926.387View
24kWIdeal Logic Max System S24£1,036.4910View
24kWPotterton Promax 24 plus system £885.351View
24kWPotterton Gold 24 System£638.082View
24kWVaillant ecoTEC plus 624 system£1,158.605View
24kWWorcester Bosch Greenstar 24i System£1,101.715View
25kWGlow-worm Energy 25kW system£907.607View
25kWGlow-worm Ultimate 3 25kW system£767.505View
25kWVaillant ecoFIT pure 625 system£1,164.562View
26kWIdeal Vogue Max System 26£1,091.6610View
26kWIdeal Vogue Gen2 System S26£1,218.418View
27kWVaillant ecoTEC exclusive 627 system boiler£1,478.905View
27kWWorcester Bosch Greenstar 27i System£1,104.985View
28kWBaxi Megaflo System 28£1,053.107View
28kWPotterton Gold 28 System£659.752View
30kWGlow-worm Energy 30kW system£936.547View
30kWIdeal Logic+ Plus System S30£966.847View
30kWIdeal Logic Max System S30£1,071.8610View
30kWVaillant ecoFIT pure 630 system£1,263.542View
30kWVaillant ecoTEC plus 630 system£1,347.915View
30kWWorcester Bosch Greenstar 30i System£1,152.555View
30kWWorcester Bosch Greenstar 30CDi Classic System£1,204.665View
32kWBaxi Megaflo System 32£1,078.607View
32kWIdeal Vogue Gen2 System S32£1,305.918View
32kWPotterton Promax 32 plus system £972.411View
35kWWorcester Bosch Greenstar 35CDi Classic System£1,344.445View
37kWVaillant ecoTEC plus 637 system£1,499.985View
50kWWorcester Bosch GB162 50kW£2,057.852View
65kWWorcester Bosch GB162 65kW£2,532.602View

Comments

  1. Dedicated servers says

    June 14, 2017 at 9:41 pm

    Typically new boiler prices range from close to 500 all the way to 2,500, so it’s important to get all the facts before you decide to buy a replacement boiler.

    Reply

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