Manual
6
Figure 3
chimney, a Top Adapter (985K) and Flashing 
are used at the top of the masonry chimney. 
The 4-inch aluminum liner is connected to 
the adapter and is passed down the chimney 
and out through the masonry wall. This 
is attached to the Retro Connector (909B) 
which is in turn, attached to the masonry wall 
and is then connected to the direct vent pipe 
leading to the appliance.
INSTALLATION INSTRUCTIONS 
FOR CONVERTING A FACTORY 
BUILT METAL CHIMNEY
Step 1.  Remove the existing chimney cap.
Step 2.  Measure the distance from the top 
end of the chimney to the bottom of the 
ceiling support box, add 3 inches to this 
measurement, and cut a section of 4-inch ex 
pipe to that length (the ex should already be 
extended to its nominal length).
Step 3.  Connect the end of the ex pipe 
section to the underside of the Top Adapter 
you have selected, using (3) sheet metal 
screws. (Figure 2.)
Step 4.  Pass the ex pipe down through the 
center of the chimney system, and center 
the adapter on the top of the chimney pipe. 
Drill (4) 1/8-inch diameter holes through the 
adapter, and into the chimney top. Insure 
that you are in fact, drilling into the metal on 
the chimney. Twist-lock the Termination Cap 
(980 or 991) onto the Adapter. (Figures 3 and 
4.)
Step 5.  Pull the ex pipe down through 
the ceiling support box, until it protrudes 
approximately 3 inches. Connect the ex 
pipe to the Retro Connector by slipping it 
into the 4-3/4-inch diameter sleeve on the 
top side of the Connector. Use (3) Sheet 
Metal Screws, to assemble these two parts.
Figure 2
Top Adapter
Flex Pipe
Sheet Metal 
Screws










