There are 3 basic types of boiler, which are available in gas or oil:

Combi boiler – directly heats both your heating and hot water

Heat only boiler – just heats the water to be supplied to your radiators and the hot water cylinder in your airing cupboard.
​
System boiler – similar to a heat only, but it contains the circulator pump within the boiler. It also allows for the small header tank in your loft to be removed.

Your house will have a certain amount of heat loss. Your system and boiler should match this rating to ensure they work most efficiently. Oversized boilers are inefficient as they deliver too much energy for the size of the system. Undersized boilers are ineffective as they won’t give you enough heat to make up for your house’s heat loss.

Ideally you should have a detailed heat loss survey on your house to ensure you’ve sized the boiler correctly. This obviously adds to the cost but may save you money in the long run. Most companies just look at the number of bedrooms and bathrooms in your house, then use their judgement on the boiler capacity. This method almost always results in oversizing.

​Boiler output is given in kilowatts. The higher the kilowatt output, the more expensive the boiler will be.

The quality of the boiler is the biggest determining factor in the cost of replacement. You can get some very cheap nasty boilers, which we do not fit and would never recommend. You’re entering a world of pain if you choose to fit a Ferroli, a Biasi, or something similar.

At the high end, you have brands such as Worcester, Vaillant and Atag. These companies have built a reputation for reliability and build quality.

Somewhere in the middle sit brands like Ideal and Baxi. If you’ve bought a new build house in the last 10 years, the chances are, it has an Ideal boiler.

​All boiler manufacturers offer some kind of reward scheme to their installers, so many companies will steer their clients towards their preferred brand. It’s wise to ask the engineer or sales person about other potential options.

You have a choice of 3 here. A full powerflush, a chemical cleanse, or a mains pressure flush.

A proper powerflush will take a full day to complete. It’s unlikely that any boiler quote you receive will include this.

A chemical cleanse is often used when new boilers are fitted. The engineer will add a cleaning chemical to the system and let it run for a while before draining the system to remove the dirty water. This is by far the cheapest option, but doesn’t clean the sludge out of your radiators very effectively,

​A system called Thoroughflush is sometimes used as an alternative to powerflushing. This uses mains-pressure water to clear debris from your system. It can target each radiator individually but takes a fraction of the time of a full powerflush.

Thermostats and programmers vary widely in quality.

Recent regulations require new systems to be fitted with higher efficiency controls. The most efficient controls use a system called OpenTherm. The control communicates the energy demand so the boiler can adjust its gas consumption and water temperature accordingly. These controls can often adjust heat output on the boiler according to outside air temperature, reducing heat demands in spring or autumn when the weather is mild.

With most boiler makes, you have to use the manufacturer’s own controls to benefit from this system.

​Smart thermostats, such as Hive or Google Nest also meet efficiency regulations and can be fitted to all systems. In most cases, they do not connect to your boiler using OpenTherm, so can only tell your boiler to turn on or off, making them less efficient.

Perhaps the hardest decision of all when buying a new boiler.

Most people rely on recommendations from friends and family to choose their installer. You’re more likely to get the personal touch from a local company. It also means that if any issues arise, you’re more likely to speak directly with an engineer. Checking reviews on Google or Facebook will give you a good idea of the reliability of these local companies.

​Some people opt for the perceived safety of a big company like British Gas or BOXT. This gives you the security of a large network of engineers, but the personal touch is lost. Should any problems occur, you’ll be calling a non-technical call centre operative.

​Like all large purchases for your home, choosing the right boiler is a big decision that will affect your home for many years. It’s important to research your options thoroughly and seek expert advice.

Choosing the right boiler for your house is a big decision. You want your boiler to give you years of reliable service, so getting the right one for your property is important.

As with most other things, you get what you pay for, so its never advisable to go for the cheapest boiler you can find.

We would always recommend choosing from one of the most trusted and renowned manufacturers.

To help you make an informed choice about your next boiler, we have reviewed 3 of the best quality boiler brands on the market.
 
Worcester Boilers

Overview:
Worcester Bosch is a highly regarded brand in the boiler industry, known for its reliable and efficient products. They offer a range of boilers for all homes of all sizes.

Performance and Efficiency:
Worcester boilers are praised for their high efficiency and robust performance. They typically feature a high efficiency rating (90% and above) and have received numerous accolades for their innovation and energy-saving capabilities.

Customer Feedback:
According to Which? reviews, Worcester Bosch consistently receives high ratings for reliability and customer satisfaction. Trustpilot reviews echo this sentiment, with many users highlighting the long lifespan, minimal maintenance needs, and excellent customer service.

Pros:

• High efficiency
• Reliable and durable
• Excellent customer service

Cons:

• Higher initial cost compared to some competitors

Vaillant Boilers

Overview:
Vaillant is another leading boiler manufacturer, recognised for its commitment to quality and sustainability. They provide a diverse range of boilers suitable for various household needs.

Performance and Efficiency:
Vaillant boilers are known for their efficiency and environmental friendliness. They often incorporate advanced technology to reduce energy consumption and carbon footprint. Many models boast an efficiency rating of over 90%.

Customer Feedback:
Which? reviews rate Vaillant boilers highly for their reliability and ease of use. On Trustpilot, customers generally appreciate the efficient performance and quiet operation of Vaillant boilers. However, there are occasional mentions of installation challenges and the need for professional servicing.

Pros:

• Energy-efficient
• Environmentally friendly
• Quiet operation

Cons:

• Installation can be complex
• Professional servicing recommended for optimal performance

Atag Boilers

Overview:
Atag is a premium boiler brand that emphasises high-quality engineering and innovative design. They offer an industry-leading 18-year warranty on their boilers, as well as lifetime warranty on their stainless steel heat exchangers.

Performance and Efficiency:
Atag boilers are renowned for their exceptional efficiency, often achieving ratings well above 90%. They incorporate innovative technology to ensure optimal performance and energy savings.

Customer Feedback:
Which? reviews highlight Atag boilers for their reliability and superior build quality. Trustpilot reviews are generally positive, with customers praising the long-term performance and efficiency. However, some users mention that Atag boilers can be more expensive upfront and may require more specialised maintenance.

Pros:

• Superior efficiency
• Innovative design
• High build quality

Cons:

• Higher upfront cost
• Specialised maintenance may be required

Conclusion

When choosing between Worcester, Vaillant, and Atag boilers, each brand offers distinct advantages:

• Worcester Bosch stands out for its reliability, excellent customer service, and overall high customer satisfaction. It is ideal for those looking for a durable and efficient boiler with strong after-sales support.
• Vaillant excels in energy efficiency and environmentally friendly features. It is a great choice for eco-conscious consumers seeking a quiet and efficient boiler.
• -Atag offers premium quality and innovative design, making it suitable for users willing to invest in a high-end boiler with exceptional efficiency.

Ultimately, the best choice depends on individual preferences and specific needs, such as budget, desired features, and the importance of customer service. It is always best to discuss the most suitable boiler type and brand with heating adviser.