Natural Gas Boilers

With over 40 years experience, Cinergi are arguably the most experienced heating engineers covering the South of England, including counties such as Hampshire, Dorset, Wiltshire, Berkshire, Surrey, West Sussex & Oxfordshire
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Product Spotlight

Cinergi are offering 0% finance for up to 36 months on all new Vaillant boiler orders placed before Christmas 2020.

Get in touch today to find out more information or secure your installation date

Are You Ready For Your New Boiler?

Buying a new boiler is a big investment, which is why you want to be sure you make the right choice of boiler, as well as an installer your can trust. Cinergi we offer free, no obligation consultations to understand exactly what each client requires – we can then make a tailored recommendation to suit your need explicitly.

Types Of Boiler System – Which Is Right For Your Household?

There are 3 main types of boiler system found in domestic properties in the UK; combination, convenional and system, each of which has their own pros and cons. Here at Cinergi, we offer straight boiler swaps (if your current one is failing or becoming troublesome) and also conversions. We are always on hand to help you identify which type of system you have, and assist you in deciding whether you would like an alternative system.

Combination Boiler

  • Identifying features: Copper pipes coming out of the bottom of your boiler – usually five of them. You’ll also have no external pump or large clunky hot water cylinder.
  • Most often found in: The most popular kind of boiler in the UK, a combination boiler (people only shorten it to combi to sound cool. Including us.) is generally the boiler of choice for flats or small houses with only one bathroom. This is because running hot water from two outputs at once is pretty much not going to happen with a combi – if you start doing the washing up while one of the kids is taking a shower then expect an earful.
  • Benefits: You can get instant and unlimited hot water and heat exactly when you need it. Plus, no big bulky tanks in your attic, in fact no big bulkiness anywhere!
  • Drawbacks: As we mentioned, two hot water outputs at once is never going to go particularly well with a combi; the water pressure suffers and the whole thing is a bit of a bust.

Conventional Boiler

  • Identifying features: Count your copper pipes. A conventional boiler should have two coming out of the top and one coming out of the bottom. An even bigger giveaway though is that you’ll have a hot water cylinder and a cold water storage tank, which will be located in the loft. An external pump is a must-have for any conventional boilers.
    If you’re still confused then it might be because, like all the old greats, the conventional boiler has a lot of nom de plumes – you may have heard them called regular boilers, a traditional boilers, or open vent boilers.
  • Most often found in: Same as system boilers, you’ll find conventional boilers in large properties that require hot water from multiple outlets at once.
  • Benefits: Hot water ahoy! With a conventional boiler system there’s no problem with using the hot water from several points at once.
  • Drawbacks: Big bulky tanks in the attic. Also, if all the hot water from the tank is used then it’s necessary to wait for more to reheat, which for many people is a big annoyance.

System Boiler

  • Identifying features: The easiest way to tell is to check for copper pipes at the bottom of the boiler – a system boiler should have three all as opposed to the combi boilers five. Again, there’s no external pump for a system boiler and no external expansion storage, it’s all kept inside the boiler itself. You will, however, have a smallish hot water cylinder. System boilers are sometimes known as sealed systems.
  • Most often found in:  Bigger homes and large properties that require hot water from multiple outlets at once.
  • Benefits: There’s no big huge tank in your loft, just the water cylinder which is usually tucked away in the airing cupboard. System boilers also allow you to use hot water from several outputs at once.
  • Drawbacks: Unlike a combi, a system boiler won’t give you instant hot water, and what it does hold is limited by the size of the cylinder. When this runs out you could be left cold.

Arrange Your Survey Today

We now offer 3 different methods of providing our customers with a no obligation survey and quotation


 At Cinergi, we understand that times are changing, and therefore the way we survey and quote our projects has adjusted accordingly. We now offer no obligation quotations via both Skype and WhatsApp video calls.


There is no need to worry if you don’t know what you are looking at when it comes to heating or electrical systems; our skilled engineers will guide you through all aspects of your installation during the survey process.

Should you wish for one of our experienced team members visit your property or workplace to undertake a survey then we are happy to oblige. We also recommend a site survey for more complex projects.


Secure, Online Quoting System

Cinergi offer a secure, online quoting system that will provide you with a no-obligation quote instantly. We do not beleive in high pressure selling, and do not demand your contact informaiton in return for a quote! Give it a go by clicking the button below!

Spread The Cost of Your New Boiler with 0% Finance

Why not spread the cost of your new boiler?


Cinergi are currently offering 0% finance for up to 36 months on all new Vaillant boiler orders placed before Christmas 2020.


Our team are always available to discuss payment options should you have any queries.


After speaking to several heating engineers we decided to go with Cinergi to upgrade our old back boiler for a new Worcester Bosch combi.

We are so glad with our choice and would recommend Ian to anyone. We are delighted with the service we have received, we were never without hot water and he worked in a professional and friendly manner.

Ian’s quote was clear and itemised so we could see exactly what we were spending our money on and he was able to offer us helpful advice on the best solution for us.

Mark Dafforn


We Chose Cinergi to replace our 17 year old boiler, we contacted Ian at Cinergi through the Bosch Worcester accredited installer website with a few other companies.

We had several other companies attend but they wanted to remove some of my decking to install a soakaway buried in the ground with limestone chippings, Ian was the only one who said there was no need for that to be done – he would install a Sentinel condensafe condensate neutraliser.

Ian was very professional, friendly and knowledgeable i would not hesitate to recommend him his workmanship was fantastic.

Mike How


Cinergi  were able to fit a new boiler at short notice with a more than reasonable quote. Ian arrived as scheduled, was very friendly and knowledgeable and got straight on with the job. His workmanship is excellent plus he takes away the old boiler/rubbish, making sure the job is left tidy. During the installation I presented Ian with a separate bit of work, moving a problematic pipe for an existing radiator. He solved the issue with some clever pipework which he was able to hide leaving a perfect finish.

Overall Ian was brilliant at his job and is obviously very experienced and skilled. I would highly recommend him to anybody and we will definitely be using Cinergi in the future.

William Coomber


Cinergi is your premier partner for all your heating and energy needs.

When you work with Cinergi you are working with a team of passionate professionals with decades of cumulative experience, standing by to deliver your project.

We want your project to go smoothly and without a hitch.

Get in touch today to find out how we can help with your next project.