Which Boiler is Best for You?

Quick guide summary

Which is the best boiler for my home, how do I choose the right boiler?

We help you find which boiler is best for you. First we consider which type of boiler you need – combi, regular or system. Then we look at which boiler manufacturer offers the best boiler package to suit your requirements. There are nine mainstream boiler manufacturers in the UK, producing 100s of models of boiler with varying levels of boiler warranty. We help you identify which boiler is right for you, your home and your budget and which manufacturers give you great aftersales care. How else can we help? Research more heating topics at our Information Hub. Find a local heating company to survey from our network of local installers.

Overview of which is the best boiler for you

Which boiler type is Best?

What are the pros and cons of combi, heat only and system boilers? When is the right time to move from a heat-only (regular) to a combi boiler or a combi boiler to a system boiler? Get helpful tips.

Which boiler package is best?

Who offers a great all round boiler package? We consider prices, warranty lengths and call centre opening hours from 9 boiler manufacturers to help you find which boiler is best.

Found your boiler? What's next?

Get an estimate of installation cost with our Boiler Quote Calculator. Are you looking for flexible ways to pay for a new boiler? Read our comprehensive guide: Ways to Pay for Your New Boiler.

HOW TO USE THIS GUIDE

Using this Guide: Use this guide to work out which boiler is best for you

Boilers by type

Consider pros and cons

Which boiler package is best for you?

Identify your current boiler, what are the pros and cons?

Combi boilers

Combi Boilers – a single usually wall unit that produces heating and hot water

Advantages of a Combi boiler

  • Produces water instantaneously (no need for hot water tanks), so no long wait times for hot water
  • Frees up space in the airing cupboard or bedroom when the old hot water cylinder is removed
  • Reduces maintenance costs as the heating and hot water functions are integral to the boiler and therefore covered by the manufacturer's warranty/guarantee

Disadvantages of a combi boiler

  • Combi boilers need a good incoming water pressure to work. Avoid in properties with poor flow rates and/or poor incoming water pressure
  • Hot water flow rates are halved when two or more hot water outlets are used at the same time. This is mainly a problem in houses with two or more showers/baths. Selecting a more powerful combi boiler may overcome this

Regular Boiler

Heat Only (Regular) boilers – works with a hot water cylinder

Advantages of a regular boiler

  • Heat only boilers are very cost effective to replace
  • They work well with open vented systems and old radiators. There is a risk that a ‘sealed system’ boiler will put old radiators under too much pressure and the system will leak.

Disadvantage of a regular boiler

  • Replacing a heat only boiler means that all the external system components (e.g. hot water tank, pumps and valves) remain in place and are therefore subject to maintenance and eventual replacement.

System boilers

System boilers – works with an unvented hot water cylinder, usually found in newer homes

Advantages of a system boiler

  • System boilers are great for properties that have two or more bathrooms and showers, as the unvented tank can deliver excellent hot water flow rates to multiple outlets even if they are run at the same time. If you are extending your property you may which to consider a system boiler over a combi
  • System boilers have most of the components found external to a heat only boiler, internal to the boiler. This means a more comprehensive boiler cover under the manufacturer's warranty/guarantee

Disadvantages of a system boiler

  • A unvented hot water cylinder will not overcome poor incoming water pressure or poor internal flow rates. If you have either of these you may want to consider an open vented heat only system or boosting your flow rates with a pump or ‘mains boost’ tank.
  • If you are moving from a combi system then you will need find space for a hot water tank.

What is a back boiler?

A back boiler is a form heat only boiler. The boiler itself is located in a chimney breast with a gas fire on the front. The boiler will work with a hot water cylinder.

It is no longer possible to replace a back boiler in the chimney breast, as manufacturers have not yet been unable to meet new efficiency standards for this type of boiler. If you have a back boiler then you can either opt for a new wall hung heat only boiler else where in the house and retain your hot water cylinder or consider a combi boiler and remove the hot water cylinder, providing your hot water pressure is good enough.

Quick Guide

When to stick with or change boiler type

1. If you have old radiators or pipework buried in screed - stick with an open vented, heat only (regular) boiler
2. If you and your family have lots of showers at the same time – consider changing to a system boiler with unvented hot water tank (if your water pressure is good)
3. On a tight budget - replace your existing boiler with the same type of boiler in the same location
4. Want low maintenance costs - install a combi boiler with a 10 year warranty/guarantee from the manufacturer (providing your water pressure is good).
5. Extending your property and adding bathrooms - consider a system boiler with unvented hot water tank (if the water pressure is good)

Which boiler package is best for you?

We help you select a great boiler package from our nine boiler manufacturers.

Which boiler is best for you will not necessarily be the most expensive boiler or the boiler with the most industry accolades. We have looked a boiler packages in the round to find our ‘best buys’. Find your boiler type and then property size in the tables below find your ‘best buy’. Then read our review of boiler manufacturer opening times to make sure they are available when you need them.

Combi Boilers

1-2 BEDROOM FLAT
Budget Range Manufacturer / Model Code Price Standard warranty Free Extended Warranty Boiler output kW (Size) Litres per minute for hot water Efficiency
Main Eco Elite 25 £606 5 5 26 10.1 90%
Potterton / Titanium 24 £738 7 7 20 9.8 91%
Baxi / Duotec 24 £675 7 7 20 9.8 89%
Vailliant / EcoTEC Pro 24 £942 2 5-10 19 9.6 89%
Worcester Bosch / Greenstar Pro 25i £875 5 7 24 9.8 94%
Worcester Greenstar Compact 28CDi £1045 7 10 24 10.0 94%
2 BEDROOM HOUSE
Budget Range Manufacturer / Model Code Price Standard warranty Free Extended Warranty Boiler output kW (Size) Litres per minute for hot water Efficiency
Main Eco Elite 30 £668 5 5 30 12.3 88%
Potterton / Titanium 28 £798 7 7 24 11.5 91%
Vailliant / EcoFITpure 825 £865 2 7-10 18 12.1 89%
Ideal / Logic+ Combi C30 £830 7 7 24 12.4 90%
Worcester Greenstar Classic 29CDi £1100 7 10 30 11.0 92%
Baxi Platinum 28 £955 10 10 28 11.5 89%
3 BEDROOM HOUSE
Budget Range Manufacturer / Model Code Price Standard warranty Free Extended Warranty Boiler output kW (Size) Litres per minute for hot water Efficiency
Ideal / Independent C35 £727 5 5 24 14.5 89%
Baxi / Duotec 33 £915 7 7 28 13.5 89%
Potterton / Titanium 33 £858 7 7 28 13.5 91%
Vailliant / EcoFITpure 830 £980 2 7-10 25 14.2 89%
Baxi Platinum 33 £1100 10 10 33 13.5 89%
Vailliant / EcoTEC plus 835 £1100 5 7-10 30 14.3 89%
4-5 BEDROOM HOUSE
Budget Range Manufacturer / Model Code Price Standard warranty Free Extended Warranty Boiler output kW (Size) Litres per minute for hot water Efficiency
Ferroli / Modena 38KW £764 5 5 34 16.0 89%
Potterton / Titanium 40 £930 7 7 32 16.4 91%
Vailliant / EcoFITpure 835 £1095 2 7-10 25 16.5 89%
Baxi Platinum 40 £1225 10 10 40 16.4 89%

Regular Boiler

1-2 BEDROOM FLAT
Budget Range Manufacturer / Model Code Price Standard warranty Free Extended Warranty Boiler output kW (Size) Litres per minute for hot water Efficiency
Baxi 400 Heat 12 £669 5 5 13 x 89%
Main Heat Only Boiler 12 £480 2 2 12 x 89%
Vaillant ecoFIT Pure Regular 12 £702 2 7-10 12 x 89%
Worcester Bosch Greenstar Ri 12 £786 7 8 12 x 91%
2 BEDROOM HOUSE
Budget Range Manufacturer / Model Code Price Standard warranty Free Extended Warranty Boiler output kW (Size) Litres per minute for hot water Efficiency
Baxi 400 Heat 15 £691 5 5 16 x 89%
Main Heat Only Boiler 15 £505 2 2 15 x 89%
Vaillant ecoFIT Pure Regular 15 £733 2 7-10 15 x 89%
Worcester Bosch Greenstar Ri 15 £801 7 8 15 x 91%
3 BEDROOM HOUSE
Budget Range Manufacturer / Model Code Price Standard warranty Free Extended Warranty Boiler output kW (Size) Litres per minute for hot water Efficiency
Main Heat Only Boiler 18 £539 2 2 18 x 89%
Vaillant ecoFIT Pure Regular 18 £802 2 7-10 18 x 89%
Baxi 400 Heat 18 £720 5 5 19 x 89%
Worcester Bosch Greenstar Ri 18 £859 7 8 18 x 91%
4 BEDROOM HOUSE
Budget Range Manufacturer / Model Code Price Standard warranty Free Extended Warranty Boiler output kW (Size) Litres per minute for hot water Efficiency
Main Heat Only Boiler 24 £593 2 2 24 x 89%
Vaillant ecoFIT Pure Regular 25 £874 2 7-10 25 x 89%
Baxi 400 Heat 24 £763 5 5 25 x 89%
Worcester Bosch Greenstar Ri 27 £1,021 7 8 27 x 92%
Worcester Bosch Greenstar Ri 24 £909 7 8 24 x 92%
5 BEDROOM HOUSE
Budget Range Manufacturer / Model Code Price Standard warranty Free Extended Warranty Boiler output kW (Size) Litres per minute for hot water Efficiency
Baxi 400 Heat 30 £834 5 5 30 x 89%
Vaillant ecoFIT Pure Regular 30 £932 2 7-10 30 x 89%
Worcester Bosch Greenstar Ri 30 £1,065 7 8 30 x 93%
Worcester Bosch Greenstar Classic Cdi 30 £1,141 7 10 30 x 92%

System boiler

1-2 BEDROOM FLAT
Budget Range Manufacturer / Model Code Price Standard warranty Free Extended Warranty Boiler output kW (Size) Litres per minute for hot water Efficiency
Glow Worm Energy System 12 £712 2 2 12 x 89%
Vailliant ecoTEC plus System 12 £772 5 7-10 12 x 89%
Worcester Bosch Greenstar System i 12 £879 7 8 12 x 94%
2 BEDRROM HOUSE
Budget Range Manufacturer / Model Code Price Standard warranty Free Extended Warranty Boiler output kW (Size) Litres per minute for hot water Efficiency
Glow Worm System Energy 15 £731 2 2 15 x 89%
Vaillant ecoFIT Plus System 15 £809 5 7-10 15 x 89%
Ideal Logi+ System 15 £859 7 7 15 x 89%
Worcester Bosch Greenstar System i 15 £926 7 8 15 x 94%
Ideal Vogue System 15 £944 8 10 15 x 93%
3 BEDROOM HOUSE
Budget Range Manufacturer / Model Code Price Standard warranty Free Extended Warranty Boiler output kW (Size) Litres per minute for hot water Efficiency
Ferroli Modena HE 25S 18 £575 5 5 17 x 89%
Vaillant ecoFIT Pure System 18 £841 2 7-10 18 x 89%
Ideal Logi+ System 18 £931 7 7 18 x 89%
Worcester Bosch Greenstar System i 18i £974 7 8 18 x 94%
Ideal Vogue System 18 £1,015 8 10 18 x 93%
4 BEDROOM HOUSE
Budget Range Manufacturer / Model Code Price Standard warranty Free Extended Warranty Boiler output kW (Size) Litres per minute for hot water Efficiency
Ferroli Modena HE 25S 25 £588 5 5 25 x 89%
Ideal Logic+ System 24 £872 7 7 24 x 89%
Vaillant ecoFIT Pure System 25 £1,035 2 7-10 25 x 89%
Worcester Bosch Greenstar System i 24i £1,100 7 8 24 x 94%
Ideal Vogue Systemi 26 £1,169 8 10 26 x 93%
5 BEDRROM HOUSE
Budget Range Manufacturer / Model Code Price Standard warranty Free Extended Warranty Boiler output kW (Size) Litres per minute for hot water Efficiency
Ferroli Modena 32S 32 £669 5 5 31 x 89%
Ideal Logic+ System 30 £902 7 7 30 x 89%
Worcester Bosch Greenstar System i 30i £1,112 7 8 30 x 92%
Ideal Vogue System 32 £1,256 8 10 32 x 93%
LARGER PROPERTIES
Budget Range Manufacturer / Model Code Price Standard warranty Free Extended Warranty Boiler output kW (Size) Litres per minute for hot water Efficiency
Potterton Promax System 32 £948 2 2 34 x 89%
Baxi Ecoblue System 30 £1,137 7 7 35 x 89%
Worcester Bosch Greenstar System Cdi 35 £1,245 7 10 34 x 92%
Vailliant ecoTEC Plus System 37 £1,312 5 7-10 37 x 89%

Are they open when we need them?

If your boiler breaks down during the warranty period then the boiler manufacturer should attend to repair it, free of charge. It is typical that a boiler will breakdown at weekend or over a bank holiday, probably because it is when we are at home, so the opening hours of the call centre are important! We have reviewed call centre opening hours for nine manufacturers to see who is available when you need them.

ExpandClose Table
Call Centre Opening Hours
Call centre opening hours Ideal Potterton Vaillant Baxi Ferroli Glow Worm Viessmann Worcester Bosch Main
Mon - Friday 8am–6pm 8am–6pm 7.30am–7pm 8am–6pm 8.30am–5pm | Friday 8.30am–3.45pm 7.30am–7pm 8.30am–5pm 7am–8pm 8am–6pm
Saturday 8am–4pm 8.30am–2pm 8.30am–3pm 8am–2pm Closed 8am - 3pm 9am–2pm 8am–5pm 8.30am–2pm
Sunday bank holidays 8am – 12pm 8.30am – 2pm 8am – 12pm 8.30am – 2pm Closed 8am - 12pm 9am – 2pm 9am – 12pm 8.30am – 2pm
Call centre closed Christmas
day
Never
Closed
Christmas
day
Never
closed
Closed on all bank holidays Chistmas
day
Closed on all bank holidays with the exception of Good Friday and Easter Monday Christmas
day
Nevr closed
Call centre location Hull Warwick Belper, Derbyshire Warwick Burton on Trent Belper, Derbyshire Telford Worcester Warwick
Phone number 01482 498 660 0344 871 1560 0345 602 2922 0344 871 1545 0330 205 0005 0345 602 2922 01952 675 060 0330 123 9559 0344 871 1570
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