Remember, when hvac contractors use rules of thumb to size air. Typical hvac rules of thumb abraxas energy consulting. Central airconditioning chilled water system with air cooled condensers capacity ranges of 20 to 400 tr, suitable for an area of 4000 sqft and higher 5. A ton of cooling load is actually 12,000 btu per hour heat extraction equipment. Correction for the density is not needed however in air conditioning cooling or applications, if the temperature is between 40f to 100f and up to ft.
Rules of thumb are abbreviated short cuts, time savers, and. Also, if youre interested in learning even more, heres a free download for you. Hvac equations data and rules of thumb third edition pdf download. The final load is than used to size the hvac equipment. If you have multiple floors, then add up all the air conditioned area for all floors and insert a single number for the hvac building area value. Book download link provided by engineering study material esm. Hvac equations, data and rules of thumb by arthur a. In addition, the experienced engineer or designer may find this manual useful as a quick design reference guide. Rules and rules of thumb for duct systems educated guesses and past experience with trial and error apply when using rules of thumb. Useful collection of handy thumb rules for quick assessment of hvac systems.
Hvac equations, data and rules of thumb by arthur a bell. Designing heat pump duct systems with correct velocity and. In the sample office building above, you would use the 110,000 ft2 value in the hvac rule of thumb calculator. Coordination of hvac and fire detection and alarm system 74. For example, if the cooling required is 30 tons 360,000 btus, then the max heating capacity required would be 612,000 btus 1. Hvac equations, data, and rules of thumb presents a wealth of stateoftheart. Central airconditioning chilled water systems with outdoor water cooled condenser capacity ranges 20 to 2000 tr, suitable for an area of 4000 sqft and higher. Hvac design thumb rules air conditioning heating, ventilating. This rule of thumb states that the max heating capacity required for your comfort cooling application is 1. A btu british thermal unit is the amount of heat needed to raise one pound of water one degree fahrenheit. Design guide for heating, ventilating, and air conditioning systems. Please find the attachment herewith of rules of thumb for mech engineers. Hvac rule of thumb calculator engineering pro guides.