Flue Dilution

A flue dilution system is normally installed where difficulties are encountered in the provision of a conventional flue to above roof level. 

Flue dilution is only permitted for VLS (very low sulphur, i.e. <0.04%) fuels up to a total combined gross heat input rating 5.45MW nett heat input or 6MW gross heat input. However, regulations recommend flue dilution systems are not installed on systems with a combined net heat input greater than 2MW. 

These systems are designed on the principle of diluting the vented products of combustion sufficiently to reduce the CO2 content to the required level of below one per cent.  Fresh air and products of combustion from the boilers are drawn into a duct by a fan and consequently diluted, thus maintaining the low CO2 discharge levels, enabling safe discharge at low level. We also provide design advice on noise and plume reduction methods. 

We carefully design each system ensuring compliance with the Clean Air Act and Environmental Health Noise Control requirements.

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Case Studies

Chimney and flue
Client to have new boilers and CHP plant installed at Telford Ice Rink complete with new flue systems discharging above roof level in accordance with the Clean Air Act. The final confirmed discharge...
Telford Ice Rink
Furanflex Installation

Client had to have existing boilers replaced over a weekend to ensure continuation of heating during the heating season. The old boilers were pressure jet, and the combined flue d...

Anglo-European Chiropractic College