F.Install Decorative Ceiling Components (SLP only)

A decorative ceiling thimble can be installed on a flat ceil- ing through which the vent passes. The decorative ceiling thimble is used to cover the firestop.

Seal the gap between the vent pipe and firestop using silicone with a minimum of 300ºF continuous exposure rating to prevent cold air infiltration.

Install the decorative ceiling thimble by sliding it up to the ceiling and attaching it using the provided screws.

A decorative cathedral ceiling support box can be used where vertical vent runs pass through a cathedral ceiling.

Use a plumb-bob to mark the center line of the venting system on the ceiling and drill a small hole through the ceiling and roof at this point. Locate the hole and mark the outline of the cathedral ceiling support box on the outside roof.

Remove shingles or other roof covering as necessary to cut the rectangular hole for the support box. Cut the hole 1/8 in. (3 mm) larger than the support box outline.

Lower the support box through the hole in the roof until its bottom is at least 2 in. (51 mm) below the ceiling (Figure 10.12).

Level the support box both vertically and horizontally and temporarily tack it in place through the inside walls into the roof sheathing.

Use tin snips to cut the support box from the top corners down to the roof line and fold the resulting flaps to the roof. See Figure 10.13.

Nail the flaps to the roof AFTER running a bead of non hardening sealant between the flaps and the roof.

WARNING! Risk of Fire! Clean out ALL materials from inside the support box and complete the vertical vent run and termination.

Level

Cathedral ceiling

support box

2 in. (51 mm)

minimum below

finished ceiling

Cut hole 1/8 in. (3 mm) greater in size than pattern of support box as it is projected onto roofline.

Figure 10.12

Figure 10.13

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Heatilator • Novus NNXT • 4055-879 • Rev. o • 2/12

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Heatiator NNXT3933IL, NNXT4236IL NNXT3933I owner manual Install Decorative Ceiling Components SLP only