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Gas Safe Register is the official gas registration body for the UK, Isle of Man and Guernsey, appointed by the relevant Health and Safety Authority for each area. By law all gas engineers must be on the Gas Safe Register.

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How do boilers work?

Unless your boiler is broken, the chances are you’ve probably not given much thought to how it actually works. It can be useful to have some idea as to how your boiler works so that you’re prepared if it suddenly breaks down.

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Price Guarantee[28]

Simply answer a few multiple choice questions about your existing boiler and we’ll give you a fixed price for a new boiler including all parts and installation[28]

Exclusive online discount!

Your boiler works at the heart of your central heating system to send heat and hot water to the radiators and taps in your home. There are many parts to a boiler and each type of boiler works differently, so unless you’re a gas safe registered engineer, it can be confusing to know exactly how boilers work.

As a basic understanding your boiler will burn a mixture of gasses together in a pressure vessel to heat your water and radiators. The boiler is the most important part of a central heating system as it is the big fire that powers all other parts. Most boilers are powered by gas and connect through a pipe to the gas main in the street. This allows the boiler to have a continuous supply of natural gas streaming into it so it is ready to light up whenever you choose to turn it on. It is possible to have other fuel types powering your boiler such as oil, LPG, and electric.

Both gas and oil fired boilers use controlled combustion of the fuel to heat water. The most important parts of a boiler that affect how well it works in this process are the burner, heat exchanger, combustion chamber and controls. The burner will mix together the gasses and oxygen so that they are able to burn more effectively and provide energy to heat your home. Hot water and heat that is produced by the boiler is then pumped through the pipes to supply the radiators and taps.

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[28] Exclusions apply. See www.help-link.co.uk/fixed-price-quote-faqs/

[79] 5% online discount is available to domestic gas customers who receive an online quote for all boiler brands excluding the Ideal Logic HE24, HE30, HO15, HO18 & HO24 and Worcester Bosch 25i ERP, 30i ERP, 15ri, 18ri, 24ri, 30 CDI Classic & 40 CDI Classic boilers which qualify for the winter bundles offer. £50 additional discount available on all like-for-like system swaps and a £100 discount is available on conventional to combi, and combi to conventional boiler swaps. Online discounted price is only available for the duration of the 14-day quote validity which starts from the day the quote was given. Help-Link UK Ltd include a filter as part of your quote as this is highly recommended by the boiler manufacturer as a key component in maintaining boiler health, functionality and may potentially be looked upon favourably by manufacturers when assessing warranty work. This filter can be removed at the customer’s request. Quote also includes a programmable thermostat for all combi boiler installations as this is a legal requirement as part of the Boiler + legislation introduced 6th April 2018, and cannot be removed from the installation unless; it is replaced with an alternative smart thermostat; or another energy saving measure as listed in the Boiler + legislation or if a smart thermostat already exists within the property. Offer is not available to Help-Link UK Ltd or HomeServe group employees. This offer cannot be used in conjunction with any other offers. Help-Link UK Ltd have the right to withdraw or change the offer at any time. Online discount is automatically applied when the customer gets a quote using the online quote system at help-link.co.uk and as long as the customer meets all the above criteria.