Riello Array AR 399 SE Installation, Operation And Service Manual page 64

APPENDIX
APPENDIX RECYCLING AND DISPOSAL
Horizontal venting system (sealed combustion); X≥4" (102
mm); Y ≥12" (305 mm)
X
2
2
1
Vertical venting system (sealed combustion); Y 12" (305 mm)
above maximum snow level or at least 24" (610 mm) which-
ever is greater
1
2 1
1
Vertical venting system (sealed combustion); X > 12" (305
mm); Y 12" (305 mm) above maximum snow level or at least
24" (610 mm) whichever is greater
X
Horizontal venting system (sealed combustion)
64 64
X
1
1
2
2
2 1