Keston S30 Matty June 1, 2023
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Keston boilers and filter
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Keston was originally established in 1928, creating domestic and commercial boilers. In 2006, Keston was purchased by Ideal Heating.

Keston boilers are manufactured in Ideal’s Hull site. As an Ideal owned company, you can expect a high level of customer service.

Keston Boilers

We’ll cover the positives of Keston boilers first to see whether or not it’s worth buying one. 

One of the advantages of Keston boilers is the ‘twin flue system’. Every Keston boiler has two flue holes to make installation simpler and give heating engineers maximum flexibility. This may not be a massive draw as a customer, but if your boiler is in a tricky position, it could be a good choice to help your engineer out.

The twin flue system can be extended up to 27 metres from the boiler itself. So if you have a massive home or you just enjoy a massive flue run then this is the boiler for you.

Another advantage Keston has is that they have the same customer service department as Ideal boilers, which is really good. So if you have an issue and you need to speak to someone, you can. They are pretty proactive at getting out to jobs as well.

Keston isn’t the cheapest boiler brand out there, despite not being a massively reliable boiler. You may be better off just going with an Ideal which is similarly priced but generally much more reliable.

Depending on the model of Keston boiler you choose, you can get up to seven years warranty, which gives you peace of mind when you buy a Keston boiler it will last for a decent amount of time.

Keston’s Trustpilot profile has a trust score of 3.3 out of 5 from just 25 reviews. 25 reviews are not really enough to go on in terms of telling how Keston customers feel about their boilers, but having 72% of reviews in the ‘bad’ section is never a good sign.

We wouldn’t recommend a Keston boiler unless you need to run a flue from a boiler located in a difficult position and you don’t want the hassle of moving the position of the boiler. This can be useful for boilers located in basements or in flats where the flue is located in the void.

Keston has a very limited range of combi, regular, and system boilers with a limited choice of kW outputs.

If you aren’t sure what boiler type you have, check out our blog, it’s important to know your boiler type before getting any boiler quotes.

Once you know what boiler type you’re looking for, you can use the WarmZilla boiler comparison function below. Just select up to 3 boilers you want to compare and you’ll be able to compare key stats side by side to see which Intergas (or another boiler brand) is best for you.

You can also take the WarmZilla survey, by answering a few simple questions about your home we will be able to recommend suitable boilers for your heating and hot water requirements. You can get a quote on a new boiler in just a few minutes without adding any personal details.

WarmZilla does not sell Keston boilers because there are better options available for the same or less money. They are also quite limited in the choice of kW options and the boiler models available. The twin flue system is useful but only in very specific situations.

Keston boiler prices vary depending on the model you choose and the kW output of the model you require. The Keston 30C (30kW) combi boiler costs £1250 (without installation) from a plumbing merchant.

From the same plumbing merchant a Worcester Bosch 4000 (30kW) combi boiler costs £1000. A pretty big saving and you get a mid-range Worcester Bosch boiler from a model that was first released in 2021.

A WarmZilla boiler comes with the boiler, Gas Safe installation, system filter, system cleanse, inhibitor, wireless thermostat, up to 14 years guarantee, any flues or extension kits you may need; plus, if your condensate or gas pipes require upgrading – that’s included in your fixed price boiler quote too!

You can get a quote now on a new boiler with all the extras mentioned above, in a few minutes using the WarmZilla online survey.

Keston boilers sit under the umbrella company, Ideal Heating. As a result of this, their boiler service checks are very similar to the way Ideal’s boiler services are carried out.

Similar to Ideal, Keston boilers are required to be annually serviced in order to keep their warranty valid. A regular service is required for all gas boilers to ensure that they are running at their full potential, meaning that they can supply the hot water and central heating that you need.

Your typical Keston boiler service will include:

  • Checking the effectiveness of your boiler case seals
  • Checking that your boiler’s gas burner pressure or conduct a gas-rate check
  • Flue gas analysis to measure your boiler’s efficiency
  • Flow and spillage test on your boiler flue to ensure that it’s working as it should be (this will depend on whether your boiler is open-flued or not)
  • Check for any gas leaks coming from your boiler
  • Ensure that all boiler safety devices are working correctly
  • Your engineer will explain what repairs or maintenance that may need to be carried out on your boiler
  • You should receive a copy of the documentation of the service or any work carried out by your Gas Safe engineer

Why should I get my Keston boiler serviced annually?

Naturally, your boiler’s efficiency will decline over time as a result of debris build-up in the system. A build-up of rust and debris can result in your boiler not working to the best of its ability. Getting your boiler annually serviced can help to avoid this. It can also help to reduce the risk of any unwanted boiler repairs and extend the life of your boiler.

The Keston S30 has an efficiency rating of 89.5% and an ErP A-rating for heat, meaning that although this system boiler is not the most efficient boiler on the market, it could still help lower your energy bills, depending on your current heating system.

With an output of 30kW for central heating, this system boiler can comfortably heat a medium-sized up with up to 20 radiators. However, if you feel that your home has a higher demand for central heating and hot water, the Keston C35 35kW Combi Gas Boiler may be better suited to your home. On the other hand, if you’re thinking about changing to a combi boiler, the Keston C30 30kW combi gas boiler is a great option. 

System boilers are ideal for homes with a high demand for central heating and instant hot water. This is thanks to the additional hot water storage cylinder which is installed alongside the boiler unit itself. This hot water storage cylinder will keep unused heated water in a sealed tank, ready to be used when you need it.

Keston boilers are typically used in compact spaces such as smaller flats/properties in locations such as London. This is because Keston boilers offer a twin flue system which makes every job easier. To give you maximum flue flexibility, you can run the flue vertically or horizontally from an elevation of 1.5 degrees and the flue can be extended up to 27 metres from the boiler.

This allows for hassle-free and easy installation and means that your new boiler can be installed in the most practical and convenient space in your home. 


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