Operating instructions

B - 1 VERTICAL THROUGH-THE-ROOF VENTING

The maximum straight vertical run of vent pipe is 36 ft. from the top of the fireplace. The fireplace will

support a maximum run of 36 ft. Maintain 1" air space clearances on all sides of vertical vent-pipe sections

and 2" clearances above any horizontal vent-pipe sections.

IMPORTANT:

REFER TO DRAWINGS ON PAGE 12& 13 WHILE FOLLOWING THESE INSTRUCTIONS.

The DXV-42 Fireplace must be installed by a qualified Mendota approved serviceperson.

1. Place the fireplace in its desired location. Drop a plum bob from the ceiling to the position of the fireplace flue

exit. Mark the location where the vent will penetrate the ceiling. Drill a small hole at this point. Next, drop a

plum bob from the roof to the hole previously drilled in the ceiling. Mark and drill the spot where the vent will

penetrate the roof. Determine if ceiling joists, roof rafters or other framing will obstruct the venting system.

You may wish to relocate the fireplace or to offset, to avoid cutting load bearing members.

2. Cut and frame a 10" x 10" opening in the ceiling centered on the hole drilled in No. 1.

3. To determine the length of the vent pipe required, measure the distance from the fireplace flue outlet to the ceil-

ing, the ceiling thickness, the vertical rise in the attic or second story and allow sufficient vent height above roof-

line. For two story installations, firestops are required at each floor level. If an offset is needed in the attic,

additional pipe and elbows will be required.

4. Assemble the desired lengths of vent pipe and elbows to reach from the fireplace flue outlet. Ensure that all pipe

and elbow connections are in their fully twist-lock position and are leak-proof. Maintain 1" airspace clearances

to combustibles (2" above horizontal runs). Be sure 2000º sealant is used on the inner pipe joints of all

Duravent pipe sections.

5. Cut a 9" x 9" opening in the roof, centered in the small drilled hole placed in the roof in No. 1. The opening

should be a sufficient size to meet all clearance requirements. Continue to assemble lengths of pipe and elbows

necessary to reach up through the roofline. Galvanized pipe and elbows may be utilized in the attic, as well as

above the roofline. The galvanized finish is desirable above the roofline due to its higher corrosive resistance.

a) If an offset is necessary, it is important to support the vent pipe every 3 ft. to avoid excessive stress on the elbows

and possible separation. Wall straps are available for this purpose.

b) Whenever possible, use 45º elbows instead of 90º elbows. The 45º elbow offers less restriction to the flow of

flue gases and intake air. If a 90º elbow is necessary there must be a minimum of a one-foot pipe section rise from

the 90º elbow to the vent cap or to the next offset. A maximum of three (3) 90ºelbows are allowed per installa-

tion.

6. Slip the flashing over the pipe sections protruding through the roof. Secure the base of the flashing to the roof

with roofing nails and seal flashing to roof. Ensure the roofing material overlaps the top edge of the flashing.

Verify you have at least the minimum clearance to combustibles at the roofline.

7. Continue to add pipe sections until the pipe and the vent cap meet the minimum building code requirements, as

outlined in No. 8 on the following page.

a) For multi-story vertical installation, a ceiling firestop is required at the second floor and any subsequent floors. The

opening should be framed to 9" x 9" inside dimensions as described in step No. 5.

b) Any occupied areas above the first floor, including closets and storage spaces, which the vertical vent passes

through, must be enclosed. The enclosure may be framed and sheet rocked with standard construction materials,

however, be sure to maintain minimum allowable clearances between the outside of the vent pipe and the combus-

tible surfaces of the enclosure.