If you have an older non-condensing boiler, your emissions will be higher and the efficiency could be as low as 65 – 70 % depending on the manufacturer and how badly the baffles may have distorted, or not. A new non-condensing or condensing boiler will give you efficiencies of between 87 – 93% on average. If you’d like to know more, have a look at our condensing and non-condensing page.

A non-condensing boiler has a single heat exchanger chamber, where the hot gases from the burner, pass through to heat the water within the walls of that exchanger, before reaching the exit flue. The construction consists of a basic combustion chamber at the bottom half, followed by a network of baffles which guide the hot gases around the walls of the top half of the exchanger, until they reach the exit flue.

A condensing boiler operates in exactly the same way, but before the hot gases reach the flue, they go through a secondary stainless steel heat exchanger, which effectively lengthens the heat transfer time and so potentially resulting in better efficiency.

Non-condensing boilers are acceptable if it would be too difficult or costly, to install a condensing boiler in a property. To find out whether you meet the criteria for a non-condensing boiler, have a look at our installation exemptions page or give us a call on 01952 270082, we can help.

Many people don’t realise that it is still legal to fit a non-condensing boiler if two specific criteria are met.

Firstly, you have to obtain an exemption and for more information on this, click here.

From September 2015, any non-condensing boiler fitted in the UK has to reach a minimum standard of efficiency of 86%. Only Mistral Energy Products have achieved this standard at this time. So if you’re being informed that you can’t have a non-condensing boiler, it may be that the model you’re considering does not comply with the standard.

Please contact us if you are in doubt.

Every time your burner initially fires, it creates very minute particles of soot, which can cling to the internal sides of the heat exchanger and this can gradually build up over a period of time.

If left, it can get to a stage where more and more particles are attracted to this area and this can have an affect on the operation of the boiler.

Over this period, there is also the throughput of fuel, which wears the nozzle hole larger allowing more fuel to pass through and this can change the combustion settings.

Consider an outdoor boiler or locating a boiler in a garage if you have one. All our products can be purchased as indoor, outdoor, condensing or non-condensing boilers.

If you have a boiler outside of your property, you have no fumes, no smell, no mess, no servicing indoors and no having to wait for the engineer to arrive!

No, it has to be stainless steel or plastic, depending on the output.

Having a combi is a compromise – you no longer need a tank, which may have been located in an airing cupboard, and this is replaced with a more instantaneous amount of hot water, created within the boiler. The compromise is that the water you get is lower in volume to what you may have been used to, and also proportionate to the output of boiler you have installed.

As a rule of thumb, a boiler is sized for the heating capacity of the building, not necessarily for how much water you need. Combi boilers are usually only available up to 35kw models, however, Mistral boilers are manufactured from 15 – 70 kw.

As an example of power, our 41kw boiler, which is the same size as a 15kw boiler, can produce almost twice as much water as any other manufacturer’s combi boiler on the market at the present time.

Generally speaking, all our boilers can be purchased through all National and Independent merchants throughout the UK. If you need any advice, please feel free to contact us directly and we will recommend someone usually in your area.

You can buy genuine spares directly from us, or your local merchant, whichever is easiest for your circumstances.

It is unlikely that your boiler at this age was made to the standard to accept the pressure, however, you should check with the original manufacturer.