Help installing roof top unit

[altzinc]

I mounted unit onto the roof but dont know how to connect ducts to it. What material to use to insullate it?

[rabadger]

It depends on the type of unit. down discharge, side by side, side discharge with bottom return.

Is it on a curb.

Need more info on this one.

[altzinc]

Yes it is on a curb. Its goodman heathing+ cooling system/ down discharge. I have 5 rooms to supply to but don't know where to begin.I have a possibility of getting to the unit from the inside of the building , if it makes it any easier :?:

[rabadger]

1. You have to know how much cfm is required for each room.

2. You have to know how much heating and cooling is needed for each
room in BTUH

3. Next you have to know the CFM and BTU outputs of the unit.

4. Next you have to size the ductwork accordingly to deliver the required amount of air in CFM at the proper velocity.

5. Next you have to figure out what to do with the excess CFM that is not needed if the unit has to much capacity.

6. After you have all of the above on paper and a source for the sheet metal and special fittings that may be required you can start to proceed.

I don't know of any other way of doing it and getting it right.