Monessen Hearth KHLDV400 User Manual
Page 12

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73D0024
KHLDV Series Gas Fireplace
VentInG InStaLLatIOn
InStaLLatIOn pLannInG
There are two basic types of direct-vent installation:
•
Horizontal Termination
•
Vertical Termination
It is important to select the proper length of vent pipe for 
the type of termination you choose. It is also important to 
note the wall thickness. 
FOr HOrIZOntaL terMInatIOn
Select the amount of vertical rise desired. All horizontal run of venting must have 1/4" rise for every 12" of run 
towards the termination. 
You may use up to three 90° elbows in this vent configuration. Refer to Vertical/Horizontal Termination Con-
figurations on Pages 17 and 18.
FOr VertIcaL terMInatIOn
Measure the distance from the fireplace floor to the ceiling. Add the ceiling thickness, the vertical rise in an 
attic or second story, and allow for sufficient vent height above the roof line. 
nOte: You may use two 45° elbows in place of a 90° elbow. You must follow rise to run ratios when using 
45° elbows. The appliance is approved for use with three 90° elbows maximum or a combination of 90° and 
45° elbows up to a maximum of 270°. 
For two-story applications, firestops are required at each floor level. If an offset is needed in the attic, additional 
pipe and elbows will be required.
You may use a chase with a vent termination with exposed pipe on the exterior of the house. See Installing A 
Vent System in an Outside Chase below. If pipe is enclosed in chase, it is not exposed. 
It is very important that the venting system maintain its balance between the combustion air intake and the 
flue gas exhaust. Certain limitations apply to vent configurations and must be strictly followed.
InStaLLInG a Vent SySteM In an OutSIDe cHaSe
A chase is a vertical boxlike structure built to enclose venting that runs along the outside of a building. A chase 
is required for such venting. 
w
arn
In
G
never run the vent pipe level or downward. 
this may cause excessive temperatures which 
could cause a fire. 
n
O
t
Ice
treatment of firestops and construction of the chase may vary from building 
type to building type. these instructions are not substitutes for the requirements 
of local building codes. you must follow all local building codes. 
n
O
t
Ice
when installing in a chase, you should insulate the chase as you would the 
outside walls of your home. this is especially important in cold climates. 
Insulation should be considered a combustible material. Maintain proper 
clearances to all combustible materials. 
w
arn
In
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always maintain minimum clearances around vent systems. the minimum 
clearances to combustibles for horizontal vent pipe are 3" at the top and 1" at 
the sides and bottom of the vent system until the pipe penetrates the nearest 
vertical wall (1" required). a 1" minimum clearance all around the pipe must 
be maintained at outside wall and on vertical runs. Do not pack the open air 
spaces with insulation or other materials. this could cause high temperatures 
and may present a fire hazard. 
