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Boiler Specs

Understanding boiler specs

If you are looking for a new boiler, then having an understanding of boiler specs, will help you figure out the most efficient way to heat your home. With combi, system and traditional boilers available, you will come across slightly different specifications. With that in mind, this article will include some of the key boiler specs and what they mean.

Carbon monoxide emissions

When gas boilers provide heating and hot water for your home, naturally, carbon monoxide is released throughout this process. Therefore, when you are looking for a new boiler, you want the specifications for carbon monoxide emissions, to be as low as possible. This is because a boiler malfunction or a blocked flue pipe could lead to carbon monoxide being released into your home.

As this gas cannot be seen, smelt or tasted, a carbon monoxide alarm is the only way to detect it. To limit the chances of this happening, it is a good idea to have your boiler serviced regularly, to ensure it is working properly.

Boiler efficiency

All new boilers come with an ErP rating, which stands for Energy-Related Products. This system allows homeowners to understand efficiency and compare products across different brands. Boilers with the best efficiency, are likely to save you money over the course of each year because they waste less energy.

Boiler power

Another key boiler specification you need to be aware of is boiler power. The measurement, which is shown in kilowatts, determines how much hot water and heating can be supplied to your home. When compared to the average heating unit, a powerful boiler, has the capacity to heat more radiators and provide more hot water, which is useful for larger homes.

Before purchasing a new boiler, you should make sure that the boiler’s power output can meet your needs. You can do this by judging several factors including the size of your home, the number of occupants and your energy usage habits.

Depending on your boiler’s type, the power output will be indicated through an input and output rate, referring to either just your central heating or both your heating and hot water.


With gas boilers, there are a series of specifications related to pressure. Usually, this refers to either gas or water pressure. Both play an important part in your boiler’s functioning. There is something known as minimum inlet pressure, which is the lowest pressure your gas can enter the boiler, for it to continue operating safely and efficiently. There also might be a minimum and maximum rate for water pressure. If this figure is not within the required range, then water could be getting lost through a leak in the system.

Water flow rate

Specific to combi boilers, the water flow rate determines how much hot water your boiler can send through to your taps. Generally, this is measured in litres per minute, signifying the volume of water coming from your plumbing fixtures. The more taps and showers you have in your home, the higher water flow rate you need. Especially, if you want to run them at the same time.

Worcester Bosch Boiler

Homeowners are still able to get a FREE boiler grant or insulation grant via the ECO scheme, which is still available to households that qualify. Warma UK are currently working throughout the UK helping privately owned and rented homes to improve home energy efficiency and save money on rising energy bills.

For more information email –

Or call 03304600065

Apply For Your Government Backed Heating Grant

Following your successful application, we will arrange a free, no obligation survey to ensure the maximum grant is obtained and advise you on the best products to reduce your homes energy usage.

Michael Cornish