Flex Vent Installation - MHSC DIRECT VENT MLDV500 Installation And Operating Instructions Manual

MLDV Series Gas Fireplace
1. Flexible UL1777 listed venting may be used in any venting application where rigid direct vent components can
be used. All restrictions, clearances and allowances that pertain to the rigid piping apply to the flexible
venting. Flex kits may not be modified. Flex kits may be added to the
end of a vent run made of rigid vent sections using pipe manufacturer's
approved flex to pipe adapters. This may occur only if doing so does
not violate any of the venting length, height, routing, horizontal to
vertical ratio requirements or clearance considerations detailed in
this manual.
. The flex adapter starter kit (DVFF8A/8) is used to attach flex
venting to the appliance starting collar. It includes 5" inner
and 8" outer adapter rings. Figure 36
•
The inner and outer adapter rings are required to start
all flex runs.
•
Never install damaged or torn flexible venting.
•
Over tightening clamps may rip, tear, or otherwise
damage flexible venting.
•
The adapter kit does not include individual pipe sections
which may be purchased separately. (UL1777 listed type
venting only.)
3. Start the flexible vent as follows:
A. Installing the inner flex adapter and pipe. See Figure
1.
1. Insert the long side of the 5" inner ring into exhaust pipe,
gently tap to seat into place, and secure with screws.
. Slide the small gear clamp over the inner flexible vent pipe,
and push out of the way.
3. Pull and extend the inner flexible vent.
4. Slide the inner vent onto the adapter collar, for a minimum
1 " overlap.
C\v
5. Locate the clamp at approximately 3/4" from the flex end and tighten.
6. Secure the clamped inner section with three self-tapping screws, drilled
equidistant, just above the clamp perimeter.
B. Installing the outer flex pipe. Figure 36
1. Firmly insert the 8" outer adapter ring into the outer appliance starting collar
and secure with screws.
. Slide the large gear clamp over the outer flexible vent pipe, and push out of
the way.
3. Pull and extend the outer flexible vent.
4. Slide the outer vent onto the appliance collar outer adapter for a minimum
1 " overlap.
C\v
5. Locate the clamp at approximately 3/4" from the flex end and tighten.
6. Secure the clamped outer section with three self-tapping screws, drilled
equidistant, just above the clamp perimeter.
C. Routing UL1777 flex pipe.
F l e x v e n t p i p e s p a c e r s : R e f e r t o
manufacturer's specifications for correct
positioning of the spacer springs to
maintain proper distance between inside
and outside pipe.
6

FLEx VENT INSTALLATION

1C\v" Flex-
ible Pipe
and Adapter
Outer
DVFF8A/8
Inner Adapter
Outer Adapter
Figure 36 -
Typical Appliance Connection
UL1777
FP1972
Flex Vent
appliance connection
When using a 1DA reducer, 5" x 8" to 4"
x 6B\,", the flex adapter starter kit DVFF8A/8
is used to start the 4" x 7" flex venting at the
adapter. All restrictions and allowances that
pertain to 5" x 8" flex venting apply to 4" x 7"
flex venting.
UL1777
Flex Vent
equidistant just
Appliance
Starting Collar
FP197
5° Radius
FP1973
Figure 37 -
Minimum Radius for Flex
FP1973
Vent Section
flex pipe bend
75D0004
Screws
(3 places,
above gear
clamp)