A professional HVAC contractor installing a new system has three indispensable references to consult: Manuals J, D, and S. Published by the Air Conditioning Contractors of America, this software is designed to generate the specialized data required for a successful installation and optimum system efficiency and comfort thereafter. Old-school methods of “guesstimating” installation parameters, or relying on a one-size-fits-all approach, all too frequently led to over-sized or under-sized systems that wasted energy and performed poorly for as long as they were installed in the home. Here’s how a contractor brings state-of-the-art HVAC research to the installation of your air conditioner and furnace with Manuals J, D, and S.
Manual J is the principle load calculation software utilized by HVAC contractors. Cooling load and heating load express the BTUs of heat that must be removed from the house to keep it cool or added to the house to keep it comfortably warm. This figure varies from house to house and can only be accurately determined by a load calculation conducted by a qualified HVAC technician. No new air conditioner or furnace should be installed without one. In many locales, building codes require a Manual J load calculation by law.
Manual D is utilized to design effective ductwork. Connecting a new, efficient A/C or furnace to poorly designed and/or defective ductwork is self-defeating. Manual D takes data about blower air volume and integrates ductwork variables like the total length of the span, the amount of air friction generated inside the ducts and the number of curves, joints and elbows to arrive at duct sizing specs and design recommendations for maximum efficiency.
Manual S contains a database of available makes and models of air conditioners and furnaces, keyed to specific performance data including BTU capacity and other critical characteristics of each unit. By inputting load calculation data generated by Manual J, the contractor can select the ideal A/C or furnace for your residence and local climate.
Ask the experts at Aggressive Mechanical Contractors about professional HVAC installation utilizing Manuals J, D, and S.
Our goal is to help educate our customers in Monmouth County, New Jersey and surrounding areas about energy and home comfort issues (specific to HVAC systems).
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