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3. Class A Metal Chimney
| TERMINATION |
| CAP |
| TOP |
| ADAPTOR |
| FLASHING |
EXISTING |
|
METAL |
|
CHIMNEY |
|
SYSTEM | 4 in. (102mm) FLEX PIPE |
RETRO
CONNEC TOR
DIRECT
VENT PIPE
Figure 5.20
CAUTION
Ensure that existing chimney is functionally sound and clean.
•Have inspection done by qualified chimney sweep or professional installer BEFORE converting to direct vent appliance.
Step 1.
Remove existing chimney cap.
Step 2.
Measure the distance from the top of the chimney to the bottom of the ceiling support box, add 3 in. (76mm) to this measurement, and cut a section of 4 in. (101mm) flex pipe to that length (the flex should be fully extended).
Step 3.
Connect the end of the flex pipe section to the underside of the top adapter, using four sheet metal screws (Figure 5.21).
Top Adapter
Flex
Pipe
Sheet Metal Screws
Figure 5.21
Step 4.
Pass the flex pipe down through the center of the chimney system, and center the top adapter on the top of the chimney pipe. Drill four 1/8 in. (3mm) diameter holes through the top adapter, and into the chimney top. Ensure that you are drilling into the metal on the chimney. Twist lock the high wind termination cap onto the top adapter (Figures 5.22 and 5.23).
Figure 5.22
HIGH WIND
TERMINATION
CAP
SHEET METAL
SCREWS
DRILL FOUR 1/8 in. (3mm) DIAMETER HOLES
Figure 5.23
Step 5.
Pull the flex pipe down through the ceiling support box, until it protrudes approximately 3 in. (76mm). Connect the flex pipe to the retro connector, and attach with sheet metal screws.
Step 6.
Push the flex pipe back up into the ceiling support box, center the retro connector, and attach it to the support box with sheet metal screws.
Step 7.
The connection between the appliance and the retro connector may be completed with sections of direct vent pipe.
January 3, 2007 | Page 19 |