Desa CD36TN-M Continued, Thimble Installation, Vertical Termination Configurations for Top Vent

Venting Installation

instructions

Continued

5. Place the flashing over the pipe section(s) extending through the roof. Secure the base of the flashing to the roof and framing with roof- ing nails. Be sure roofing material overlaps the top edge of the flashing as shown in Figure 19, page 15. There must be a 1" clearance from the vent pipe to combustible materials.

6. Continue to add pipe sections until the height of the vent cap meets the minimum building code requirements described in Figure 9 on page 9. Note:You must increase vent height for steep roof pitches. Nearby trees, adjoining rooflines, steep pitched roofs and other similar factors may cause poor draft or down-drafting in high winds. Increas- ing the vent height may solve this problem.

7. Twist-lock the vent cap onto the last section of vent pipe.

Note: If the vent pipe passes through any occupied areas above the first floor, including storage spaces and closets, you must enclose pipe. You may frame and sheetrock the enclosure with standard construc- tion material. Make sure and meet the minimum allowable clearances to combustibles. Do not fill any of the required air spaces with insulation.

Thimble Installation

1. Plumb and locate knockout area for vent pipe.

2. Cut and frame ceiling joist to dimensions shown in Figure 11, page 11.

3. Determine where firestop plate should be at- tached to thimble by test-fitting thimble into framing. Thimble should be at or above the height of the insulation.

4. Attach thimble into firestop plate using 4 hex screws provided (see Figure 21).

5.Refit assembly into opening and attach to framing with 8 phillips screws provided (see Figure 20, page 15).

6.Thimble installation is ready to receive vent pipe. Follow venting installation instructions.

Vertical Termination Configurations for

Top Vent

Figures 22 through 25 show four different con- figurations for vertical termination.

VERTICAL VENT INSTALLATIONS USING MULTIPLE 90° ELBOWS

Note: Install a

VR-58 vertical restrictor ring into inner pipe

section prior to

attaching vent

termination cap.

90° Elbow

Top of

Thimble

Should

Measure to Top of Insullation

Framing

Hex Screw to Attach Firestop to Thimble

Venting with Three 90° Elbows

	Horizontal (H1) +
Vertical (V)	Horizontal (H2)
8' Min.	5' Max
10' Min.	8' Max
12' Min.	11' Max
14' Min.	14' Max
16' Min.	17' Max
18' Min.	20' Max
40' Min.	20' Max

Phillips Screws

Firestop to Attach Firestop to

Framed Hole

Figure 21 - Installing Thimble with

Firestop

Figure 22 - Vertical Venting

Configuration using Three 90° Elbows (Vertical Round High Wind Termination)

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