Monessen Hearth Direct Vent Gas Fireplace MDV500 - Manual (Page 24)

24 75D2523
VERTICAL THROUGH-THE-ROOF APPLICATIONS
VENT INSTALLATION
Figure 30 - Installing Restrictor Disc into Stove Collar
Restrictor
Disc
Stove Collar
Install restrictor disc as shown in Figure 30 for vertically vented applications.
Up to three (3) restrictor discs may be needed for 40' installation.
The two (2) restrictor discs suppled will work for most installations. If a third disc is needed order Part No. 56D3027.
You may use a reducer to 4"x6
5 /
8
" in vertically vented applications.
NOTICE
A restrictor disc must be installed
on any vertical termination that
is higher than 12'.