offsite component 12 can be networked to a plurality of onsite components 14 alternatively a plurality of offsite components 12 can each be linked to a single onsite component 14 wherein the offsite components 12 are positioned at the same location for convenient access to each single onsite component 14 the onsite component 14 comprises a central controller 20 and a plurality of secondary units 22 the plurality of secondary units 22 can further comprise at least one sensor unit 24 and at least one secondary controller 26 each sensor unit 24 is operably linked to environmental sensor 28 including but not limited to a thermometer a humidity sensor and a barometer the environmental sensor 28 collects measurements on the current environmental conditions within the building similarly each secondary controller 26 is operable linked to an hvac system 30 and is adapted to control the operation of the hvac system 30 according to at least one control instruction each secondary unit 22 is linked to the central controller 20 via a wireless connection 32 allowing for wireless transmission of information between the secondary units and central controller 20 the wireless connection 32 can comprise radio bluetooth wi fi or other conventional wireless technology as the secondary units 22 wirelessly communicate with the central controller 20 the central controller 20 and secondary units 22 are modular and can be replaced or updated independently of the rest of the onsite component 14 in one aspect at.