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UK NCM system type selection.

I have looked through the available options on the UK NCM System Type drop down in the UK NCM Data Wizard but none of the available systems types represent my system. What should I select?

All systems that are available for a UK Compliance calculation can be selected through the through the NCM Data Wizard.



If you have a more complex system, or systems that are not available through the wizard it may be possible to enter an acceptable ‘workaround’ by selecting a substitute system type.

The following is an FAQ from the BRE website.

If your system is not included within SBEM it would be acceptable to use a 'workaround' in order to produce results using the existing systems in SBEM. However, decisions made in this process must be justified to building control.

When using a workaround in SBEM, the aim is to calculate the CO2 output of this system in your building. To do this, it is acceptable, where a system is not included in SBEM, to substitute it with another system. If a heating and cooling system exists in the building, a heating and cooling system must be chosen in order to include cooling in the calculations.

Generally a system with the same fuel type should be chosen, if this is not possible, it may be acceptable to adjust the system seasonal efficiency in order to achieve the same carbon intensity as in the actual system. For example, where a system uses gas for FCU heating coils and an electric heat pump for an associated warm air ventilation system, it could be acceptable to select a FCU system with an electric heat pump and then increase the system COP in order to reduce the carbon intensity of the system to account for some of the heating being provided by gas.

Please note that IES technical support will not be able to help with selecting an appropriate system type for your system. You should contact your local building control officer or scheme provider for assistance.