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How do boilers work?

The most common type of boiler in the UK, gas boilers work by drawing gas from the mains supply and using it to heat water in the boiler. Water is then circulated around the house via a system of pipes and radiators.

A simple guide to the different boiler types:

Combination (Combi) boilers

Combi boilers are quite simply boilers which do two different things in combinationn. They provide both hot water and central heating.

How do combi boilers work?

Combi boilers provide hot water on demand, rather than storing hot water in a storage cylinder. When you turn on a tap or go to run a bath, the combi boiler recognises that there’s a demand for hot water and starts to heat the water as you need it.

Combi boilers are perfect for homes with limited space.

Combi boilers can be compact, cost-effective and energy- efficient. As combi boilers don’t need a water tank or cylinder, they are ideal for properties where space is precious. As a result, combi boilers are one of the most popular choices among UK homeowners.

System Boilers

System boilers keep your home warm while maintaining a constant level of hot water. System boilers need a hot water cylinder to operate and they heat the hot water and send it to the cylinder to store it for when its required.

How do system boilers work?

System boilers with hot water cylinders work by using a boiler to heat water that is then stored in a hot water cylinder. This means that you will have a constant supply of hot water.

System boilers are great for homes with multiple bathrooms.

System boilers are a good solution for homes with more than one bathroom as they are capable of providing constant hot water to any number of different hot water outlets at the same time.

Regular boilers (open vent)

Regular boilers use a hot water storage cylinder to provide central heating and hot water.

How do regular (open vent) boilers work?

Open vent or ‘regular boilers’ work in a similar way to a system boiler.. They are able to keep your home warm through a central heating system and also provide hot water through a hot water storage cylinder. Regular heating systems require a cylinder which is often kept in an airing cupboard and a cold water tank usually in the loft.

Open vent boilers are great for larger home with water pressure issue

Open vent boilers suit homes with multiple bathrooms where water pressure is low in the area. The water storage tank often located in the loft means a lot of hot water can be supplied to multiple bathrooms at the same time. They are good if water pressure is typically low in your area as the water is stored in a tank ahead of use.

How do you find the right heating system for your home?

To make sure you’re choosing the right boiler for your homehome speak to one of your local Glow-worm installer and they’ll be able to advise you on the best option.

Our installers will be able to advise you based on your current heating system, your hot water and heating demands and the area you live in. From this, the installer will be able to recommend the most suitable heating system for your property and lifestyle.