Boilers
Shop high-quality boilers from trusted brands like Ideal Boilers, Vokera, Vaillant and Baxi. At Toolstation, you’ll find gas combi boilers and system boilers compatible with most central heating systems.
What Are the Different Types of Boilers?
Combi boilers are a popular choice for many homes, heating water as you need it. They are smaller and more compact than system boilers, making them easier to install in any property.
System boilers store hot water in a cylinder after heating it, producing higher volumes on demand. They can be helpful for homes with two or more bathrooms. However, once the hot water supply has been used up, you’ll have to wait for the boiler to heat more.
Browse our full range of boilers and related accessories here, or check out our Boiler Buying Guide for more tips and advice on finding the right one for you.
How do I size a boiler for a house or building?
Boiler sizing depends on your heat load: number of radiators, insulation, number of bathrooms, and hot water demand.
Use kW rating - oversize slightly rather than undersize, but avoid huge overspec. For instance, a mid-size home might need 24–30 kW for a combi boiler. Consult heat loss calculations or use a rule of thumb per radiator/room.
Can I swap one boiler brand for another?
Yes - in many cases you can - but ensure compatibility: flue position, gas supply, pipework routing, control connections, and warranty implications. Reusing existing mounting, boiler room layout, and condensate routes can reduce installation challenges.
How often should I service a boiler?
Servicing your boiler annually is standard for most boilers. Regular servicing helps maintain efficiency, catch faults early, ensure safety, extend lifespan, and keep the warranty valid. Also check for leaks, carbon monoxide safety, flue integrity, pressure, and proper burner operation.
Product code: 66570
Vaillant ecoTEC Plus 625 25kW System Boiler Only Power
£1922.78
ex. VAT £1602.32 Each
Select from 1 option
Product code: 93141
Vokera Rear Flue Kit Compact A DIN, Vision, Evolve & Unica MAX
£85.69 was £95.21
ex. VAT £71.41 Each
Product code: 71418
EHC SLIM JIM Electric Flow Boiler 12kW
£799.00 was £861.84
ex. VAT £665.83 Each
Select from 4 options
Product code: 42669
Vaillant ecoMAX/TEC Elbow 45°
£110.18
ex. VAT £91.82 Per unit £55.09/Each
Select from 1 option
Product code: AH990
Worcester Bosch Greenstar 12Ri Boiler ErP+ LPG 12kW
£1262.16
ex. VAT £1051.80 Each
Select from 4 options
Product code: AH961
Worcester Bosch Greenstar 30i Compact System LPG Boiler 30kW
£1822.77
ex. VAT £1518.97 Each
Select from 1 option
Product code: 79295
Vaillant Flue Extension ecoMAX/TEC 1m
£81.28
ex. VAT £67.73 Each
Select from 2 options
Product code: 48150
Baxi Standard Telescopic Horizontal Flue
£122.27 was £135.85
ex. VAT £101.89 Each
Product code: 89898
Ideal Logic Max System 2 Boiler 24kW
£1739.98
ex. VAT £1449.98 Each
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Product code: 70574
Baxi Flue Extension 1m with Fixing Screws
£61.83 was £68.70
ex. VAT £51.52 Each
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Product code: 11793
Ideal Logic Max Combi 2 Boiler 35kW
£1788.44
ex. VAT £1490.37 Each
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Product code: AH956
Worcester Bosch Greenstar 30Ri Compact Regular LPG Boiler 30kW
£1691.95
ex. VAT £1409.96 Each
Product code: AH959
Worcester Bosch Greenstar 30i Compact System Boiler 30kW
£1741.03
ex. VAT £1450.86 Each
Select from 1 option
Product code: AH997
Worcester Bosch Greenstar 18Ri Boiler ErP+ 18kW
£1323.67
ex. VAT £1103.06 Each
Select from 4 options
Product code: 35227
Ideal Logic Flue Extension 0.5m
£65.03
ex. VAT £54.19 Each
Select from 2 options
