DuraVent FasNSeal 8090 Installation - Manual (Page 3)

3
LISTING
M&G DuraVent's FNS 80/90 Combination
Cat I and Cat IV gas vent system is designed
and UL listed for use with approved M&G
Duravent / Security Chimneys special gas
vent components only! Listed to applicable
portions of ULC S636/UL1738, UL1777, and
UL441.
GENERAL INSTALLATION NOTES
Read these instructions before beginning.
You must follow these installation
instructions when installing the FNS 80/90
system. This is a supplemental instruction to
other DuraVent listed instructions that are
used during this installation.
APPLICATION
The FNS 80/90 system is a tested and listed
exhaust vent for the replacement of one
Category I gas fired appliance with a high
efficiency appliance in an existing Type B
common vent system. In a typical common
vent Type B setup (Fig.1), two Category I
(Cat I) appliances vent into one common
vent that conveys flue products outside the
building. In many appliance retrofits, one
Cat I appliance is removed, and replaced
with a higher efficiency (typically a Cat
IV) condensing appliance. The new Cat IV
appliance is NOT permitted to be vented with
B Vent, but requires a vent system engineered
for a different exhaust requirement.
Condensing appliances have much lower
exhaust temperatures, which create
significant amounts of acidic condensate.
Using the FNS 80/90 solution, a special
stainless steel Cat IV liner is installed within
the existing Cat I vent. This flex handles the
Cat IV flue products, while the remaining
Cat I appliance uses the annular space
around the liner to exhaust flue products
to the outside via natural draft (Fig.2). A
patent pending termination is engineered
to provide separate exhaust exit paths for
each appliances's exhaust system (Fig.2). The
combination of these systems helps both
operate more effectively.
PRIOR TO INSTALLATION: RE-LINING
COMMON VENTED B VENT SYSTEMS
When relining common vented B-Vent (or
Table 1
Clearance to Combustibles
VENT PIPE ORIENTATION
Vertical Horizontal
Type B Gas Vent Unchanged Unchanged
The vent system must be installed in
accordance with local code requirements
and appropriate National Codes: In the
US: NFPA 54 / ANSI Z223.1 National Fuel
Gas Code or the International Fuel Gas
Code.
IMPORTANT
WARNING
CARBON MONOXIDE POISONING HAZARD
Failure to follow these installation
instructions could result in personal
injury or death
Figure 1
TYPICAL
COMMON
VENTED
CATEGORY I
INSTALLATION