HVAC system controls

New heating, ventilating, and air conditioning (HVAC) systems should be provided with controls that meet the following requirements – (a) the fixed building services systems should be sub-divided into separate control zones to correspond to each area of the building that has a significantly different solar exposure, occupancy period, or type of use; (b) each separate control zone should be capable of independent switching and control of set point; (c) the service should respond to the requirements of the space it serves. Where both heating and cooling are provided they should be controlled so as not to operate simultaneously; (d) the central plant should only operate as and when the zone requires it. The default condition should be off; and (e) in addition to these general control requirements, the systems should meet the specific control requirements and general energy efficiency criteria as given in the Non-Domestic Building Services Compliance Guide.