Residential Hvac Duct Design Example

This equal friction method of duct sizing should be adequate for normal residential furnace heating and air conditioning applications.

Residential hvac duct design example.

Includes a full worked example as well as usin. A unfortunately majority of residential hvac contractors have no idea of the heat gain loss calculations and duct design. How to design a duct system. Ordinary heating ventilating and air conditioning duct systems read air pressures at 0 4 psi or less often much less.

For example if the gauge reads 10 psig then using the above equation the absolute pressure would be 24. But what i experienced as a new residential hvac service technician. Larger volumes or higher static pressures should be dealt with on an individual job basis. That is really shocking.

Typical trunk and branch duct systems. And i ve seen a lot of times how hvac contractors changed duct designs made by engineers. Ductwork is simply an air delivery system. Number one is the heating and cooling load calculation using a protocol like acca s manual j or the ashrae handbook of fundamentals.

In this video we ll be learning how to size and design a ductwork for efficiency. You ve got to know how much heating and cooling you need for each room in btu hr. 1 psi equals 27 7 inches of water gauge. Hvac for beginners the residential forced air duct system.

The following duct sizes are based on a fraction drop of 10 inches per 100 feet of lineal duct. They don t do it and don t care.