The North Carolina State Board of Examiners of Plumbing, Heating and Fire Sprinkler Contractors have announced that the State of North Carolina is requiring load calculations to be performed and a maximum temperature differential has been established. The rules became effective January 1, 2010. The new rules state that every new HVAC system shall be designed and installed to maintain a maximum temperature differential of 4 degrees Fahrenheit room-to-room and floor-to-floor. The rules also state that this shall not be accomplished through the use of manual dampers. Therefore, zoning systems that have actuator driven dampers, like the Jackson Systems Green Zone™, are a great solution. The Green Zone™ by Jackson Systems allows the contractor to provide individual temperature control on a room-to-room and floor-to-floor basis without the end user having to adjust the dampers themselves. To learn more about the Green Zone™ from Jackson Systems, please visit our website at http://jacksonsystems.com.
These new rules are beneficial to the end user to insure that they are receiving optimal comfort and efficiency from their new HVAC system. This is also an exciting opportunity for contractors to generate additional business while providing superior comfort and service to their clients. A copy of the relevant text for these new rules is listed below:
21 NCAC 50 .0505 GENERAL SUPERVISION AND STANDARD OF COMPETENCE
(d) Every newly installed residential heating system, air conditioning system or both shall be designed and installed to maintain a maximum temperature differential of 4degrees Fahrenheit room-to-room and floor-to-floor. On multilevel structures, contractors are required to either provide a separate HVAC system for each floor or to install automatically controlled zoning equipment for each level with individual thermostats on each level to control the temperature for that level. The seasonal adjustment needed to maintain the 4 degree Fahrenheit room-to-room and floor-to-floor maximum temperature differential shall not be accomplished through the use of manual dampers.
(e) All licensed HVAC contractors are required to perform a thorough room-by-room load calculation for all new residential structures prior to installing heating systems, air conditioning systems, or both which calculations shall be specific to the location and orientation where the HVAC system or equipment is to be installed. A written record of the system and equipment sizing information shall be provided to the owner or general contractor upon request and a copy shall be maintained in the job file of the licensee for a minimum of six (6) years.
(f) When a furnace, condenser or air handler in an existing residential heating or air conditioning system is replaced, the licensed HVAC contractor is required to perform a minimum of a whole house block load calculation. When a furnace, condenser or air handler in a residential heating or air conditioning system is replaced, it is the responsibility of the licensee to ensure that all systems and equipment are properly sized. The licensee may utilize industry standards, reference materials, evaluation of the structure, and load calculations. A written record of the system and equipment sizing information shall be provided to the homeowner, owner or general contractor upon request and a copy shall be maintained in the job file of the licensee for a minimum of six (6) years. If a load calculation was not performed or if a load calculation was performed and it is later determined by the Board that the unit installed was undersized or oversized, the installation will be considered as evidence of incompetence.
