White Mountain Hearth DVCX(36,42)FP30(N,P)-2 Installation Instructions And Owner's Manual page 17

Vent Pipe Clearance
Note: Maintain two inches of clearance around vertical vent pipe
on first twelve inches. See Figure 18.
For horizontal vent, maintain a minimum one-inch clearance to
the bottom and sides of the vent, and three-inch clearance to
combustibles above the vent pipe. See Figure 19.
NOTE: A two-inch clearance around pipe for the first twelve inches
above the fireplace is required.
Finish the joint between the fireplace and wall with sealant rated
at 300 degrees F, or tile/stone over the joint.
Horizontal Vent Clearances - Figure 19
35009-2-1015
INSTALLATION (continued)
Figure 18
Flush Wall Installation - Figure 20
Combustible Surround Installation - Figure 21
Attention: Cold climate installation recommendation: When
installing this unit against a non-insulated exterior wall, the outer
walls should be insulated to conform to applicable codes.
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