The following duct sizes are based on a fraction drop of 10 inches per 100 feet of lineal duct.
Hvac ductwork attic ductwork layout.
Chapter 4101 2 6 duct systems.
Remodeled home attic mounted hvac unit return box mounted approx 18 from side of ahu end has 20 flex duct attached and run in a big loop 10 15ft around to the end of the ahu.
The attic ductwork is flex duct work.
Make sure your hvac contractor follows these duct design best practices and principles using manual d.
I called out the original hvac company and they took a look and said they saw no water.
There are a few different elements to efficient design.
Use ducts for all air distribution do not use building cavities such as walls or raised floors.
The layout and installation of the duct system will incorporate these basic principles of good ductwork design.
Place ducts on top of joists in a ceiling or attic.
Larger volumes or higher static pressures should be dealt with on an individual job basis.
Make the layout as symmetrical as possible with branch ducts spaced evenly along the trunk duct and each branch of similar length.
Route ducts between joists in a basement if possible or over them if necessary.
It was new when the ac was put in 7 years ago.
Situate the air handler close to the center of the layout to minimize the length of ductwork spans.
Recently i had another hvac company come out and put in a new bathroom vent and they told me they believed the duct work was full of water.
Ductwork components consist of ducts air supply registers return grilles insulation and sealing tape or cement.
For an efficient layout.
Avoid any hot elements such as water heaters heater or stove.
After all it s hard to get cold air from a warm pipe.
This equal friction method of duct sizing should be adequate for normal residential furnace heating and air conditioning applications.
To promote balanced air circulation through the supply ducts home and return ducts the ductwork should be simple in layout accurately sized sealed insulated in unconditioned spaces and installed in the right places.
For hvac duct systems located in the attic sealing and insulating the attic with spray foam insulation is the only way to protect the system from the extreme temperatures we live with here in metro atlanta.
Wouldn t it be better to just have the duct run directly 18 to the ahu.
Contractors can make the mistake of failing to consider the type of air conditioning system you have load requirements of different rooms where ducts and equipment are located and the materials used.
Ductwork design mistake 1.