I'm planning a project that involves replacement of an air handler.
The outlet (base) will fit perfect. However the new air handler is 3-4" lower then the unit it is replacing and the inlet is 19.5 X 19.5. My return air plenum is 20.5 X 18.5.
Here are my questions:
1. What is the professional way of modifying the existing plenum to new air handler. I assume making a custom sleeve out of galvanized sheet metal is the best approach? What about insulated duct board? Is fiberglass tape and mastic the best seem method? How do professionals in the field handle slight form factor differences?
2. The new air handler will set on top of a sheet metal base. I assume that some form of gasket or sealant should be used where the air handler bottom contacts the base. What is the preferred method of sealing the contact of these two surfaces? Or is it even done?
I'm striving to do things using the best known industry methods and practices vs. the duct tape method.
I've also observed some other installations where it looks like they used some form of flexible material (almost like canvas) to mate the air handler to plenum.
The outlet (base) will fit perfect. However the new air handler is 3-4" lower then the unit it is replacing and the inlet is 19.5 X 19.5. My return air plenum is 20.5 X 18.5.
Here are my questions:
1. What is the professional way of modifying the existing plenum to new air handler. I assume making a custom sleeve out of galvanized sheet metal is the best approach? What about insulated duct board? Is fiberglass tape and mastic the best seem method? How do professionals in the field handle slight form factor differences?
2. The new air handler will set on top of a sheet metal base. I assume that some form of gasket or sealant should be used where the air handler bottom contacts the base. What is the preferred method of sealing the contact of these two surfaces? Or is it even done?
I'm striving to do things using the best known industry methods and practices vs. the duct tape method.
I've also observed some other installations where it looks like they used some form of flexible material (almost like canvas) to mate the air handler to plenum.