Manual J, D, & S Reports
Manual J Reports
The simplest way to see what a manual J report is, is to imagine a house plan of the heating and air condition load you will need to cool your home. We use the wright soft design program for doing this for you. We input the kind of wall, the type of insulation in that wall, type of sheathing and each window (with its size, its heating/cooling load, and its solar heat gain coefficient), the height of the walls, the orientation of the wall, the kind of floor (wood or concrete), roof type (even to what color of shingles you are going to have), and lastly the type and amount of insulation in the floor and ceiling.
Manual D Reports
Once the heating and cooling load are found for the various rooms of the home, one will need to place the furnace, determine friction loss, and the duct layout. When that is done the program will give you the size of all the duct piping necessary to get the correct heating or cooling load to each room or area. So now we know exactly what is necessary no more guessing or using the old rule of thumb for sizing. On many older homes the cooling load is not correct and causes the occupants to be uncomfortable and also a lot more wear and tear of the system leading to a shorter equipment life. Bottom line cheaper to install, less maintenance, and more comfort.
Manual S Reports
This is pretty straight forward. This part of the program is where the information above is collected and the furnace is sized. A furnace too big will start to stop usually leaving some cold and hot spots in the home. With the air conditions a unit too big will not get rid of the moisture on the coils before it shuts down. It will also short cycle the unit, causing the unit to not last as long. The bottom line is less cost to install a correct unit, lower maintenance on the units, and better comfort. The only drawback is an old timer that will say well I have been doing this for 30 years and it works. Well just how many of you want to go back to the old days of the Model A Ford. It did work but today’s cars go further, faster, and have a lot more comfort.
