PSG CADDY ALTERNA II Installation And Operating Instructions Manual page 27

C. VERTICALLY INTO EXISTING CHIMNEY SYSTEM
As an alternative, the 4" vent can be run inside existing chimney to termination.
NOTE: Follow the vent manufacturer's instructions.
1. Have the chimney inspected by a qualified chimney sweep or installer to determine its structural condition.
2. You will need a pipe length equal to the chimney height from its point of insertion into the chimney.
3. Make sure that the flashing is ventilated.
D. VERTICALLY INTO EXISTING MASONRY CHIMNEY
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