Why use Underfloor Heating With Combi Boilers?

Using underfloor heating with combi boilers is a great system to have. They are much more efficient and it will increase the life span of your boiler.

underfloor heating with combi boiler

Once you have decided to install underfloor heating in your home, you need to consider the method by which your system will be heated.

In most cases a boiler already exists within a property.  Therefore the design is easily drawn up to incorporate this.

Using underfloor heating with combi boilers is a great way of heating a system comprised of both underfloor heating and radiators.  This is because the boiler can reach the temperatures necessary to heat both emitters.

Underfloor Heating With Combi Boilers: Building Regulations:

Current building regulations dictate that each and every gas and oil boiler, which is installed for domestic and small commercial uses, must be of the condensing variety.

This means they ought to be capable of operating under conditions in which the heating circuit return temperature is lower than the dew point of the gases produced (by the combustion of the fuel).

Therefore, the latent heat associated with the water produced by combustion of the fuel can be used for extra input to the system.

Underfloor Heating With Combi Boilers: Improved Efficiency:

The potential improvement of efficiency for condensing boilers is partly bigger than the latent heat effect.

This is because when older boilers were designed, they were purposely restricted in terms of their efficiency.

This was to limit the likelihood of inadvertent condensation that could result in the corrosion of parts of the heat exchanger.

However, condensing operation only occurs when the return temperature is low.

For a conventional radiator system, that will mostly occur during the foremost section of the heating time, whilst the system remains in its cold state.

Underfloor heating systems, however, allow the boiler to work in condensing mode for most, if not all, of the time, and therefore they maximise boiler efficiency.

Condensing boilers are usually fired using oil or gas, whether LPG or natural gas. On larger output units, the burners are fitted with modulating controls to match the heat demand as closely as they are able to. The effect of this is that fuel consumption and carbon dioxide emissions are significantly reduced.

Using Underfloor Heating With Combi Boilers Increases the Life Span of Your Boiler:

In cases where an underfloor heating system is connected to a conventional non-condensing boiler, careful consideration must be given to the heating circuit design to avoid low return temperatures and frequent cycling under low load conditions.

Both of these will be detrimental to the life of the boiler if allowed to occur. This situation could occur where an underfloor heating system is added to an existing heating system using other emitters such as radiators.

Installing underfloor heating with combi boilers is the best system you can have, and if at all possible you should choose this.


Image: Fires Fireplaces Stoves 

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