Room Emitter

bm rooms
 hp emitter


The room detail window contains information for the volume of the room, ventilation air changes and the heat loss.

  • An accurate heat loss figure is only available after you have entered the construction elements applicable to the room.
  • Select the room type from the drop-down list - this will automatically allocate the appropriate ventilation air change figure.

Additional options are available where a building is in an exposed position, such as on top of a hill, by a riverside or on the coast. where appliances with open flu's are installed in a room the change rate is increased to allow for the movement of air into the chimney.

Heat Emitters

Determine the rated output of the existing radiators at a mean water to air temperature difference of 50°C using manufacturers' information or you can use the default options available in the software. There are a variety of standard radiator sizes available in different formats alternatively if you have the manufacturers information you can choose to enter the rated output at 500C. If only have the rated output at 600C choose the option for "rated output at 600C" and the software will automatically adjust the rating for a 50 degree comparison. 

The oversize factor is calculated where oversize factor equals the rated output divided by the room heat loss and the star rating is calculated from the oversize factor. The Temperature Star Rating can be improved by:

  • Reducing the room's fabric and ventilation heat loss;
  • Increasing the rated output of the heat emitter by adding or replacing radiators; or
  • Switching to a different emitter type.

It is important to note that the emitter selection should only be carried out once the room ventilation and heat loss has been completed otherwise limited size will be invalid.