GMES8 GCES8 Installation Instructions

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• M asonry chimneys with no air gap between the liner and
the bricks. (In practice, this can be difficult to detect.)
• Exterior chimneys (The tables in National Fuel Gas Code
NFPA 54/ANSI Z223.1 - latest edition and in the National
Standard of Canada, CAN/ CSA B149.1 and CAN/ CSA B149.2
- latest editions and amendments assume interior
chimneys.)
If, in the judgment of the local gas utility, installer, and/or local
codes; one or more of the above factors is likely to present a
problem, the chimney must be relined (Fix 4).
FIX 1 - LINER TERM INATION
Any cap or roof assembly used with a liner must be approved by
the liner manufacturer for such use. The liner and cap/ roof as-
sembly must then terminate above the roof in accordance with the
manufacturer’s instructions.
In some cases, a shorter extension above the roof may be possible
with a liner than would be required with a masonry chimney.
For further information on relining, see Fix 4.
FIX 2 -CHANGE VENTING ARRANGEM ENTS
If the masonry chimney has more than one channel, it may be
possible to vent the gas appliances into one channel and vent the
solid or liquid fuel appliance(s) into another channel(s). Do not
vent an 80+ Furnace inside of a metal liner with other appliances
vented outside the liner.
Alternatively, the homeowner may agree to discontinue use of the
fireplace (solid fuel appliance). If so, the tile liner must be cleaned
to remove creosote buildup. The fireplace opening must then be
permanently sealed.
If oil-fired appliance(s) are being replaced by gas-fired
appliance(s), the tile liner must first be cleaned to remove the fuel
oil residue.
If none of the above options is practical, the furnace may need to
be vented vertically with a B Vent.
Under some conditions, a 90%+ furnace could be installed rather
than an 80% furnace. The 90%+ furnace can be vented horizontally
or vertically through PVC pipe.
FIX 3 - REBUILD THE CROW N
If the chimney crown is damaged, a qualified mason must repair
it in accordance with nationally recognized building codes or stan-
dards. One such standard which may be referenced is the Stan-
dard for Chimneys, Fireplaces, Vents, and Solid Fuel Burning Ap-
pliances, ANSI/ NFPA 211.
FIX 4 - RELINING
Relining options include B vent and flexible liners.
If the chimney has diagonal offsets, B vent probably cannot be
used.
Flexible liners should be hung straight or nearly straight. If it is
spiraled in the chimney and in good condition, it should be rehung.
To do this, break the top seal; pull up and cut off the excess liner
length, and refit the top seal. Use caution when doing this, as the
cut edges of flexible liners may be sharp.
The surfaces of the liner must be physically sound. If gaps or holes
are present, the metal liner must be removed and replaced (Fix 4).
Finally, confirm that the metal liner is the correct size for the
appliances to be installed. Use the GAM A tables and rules.
If a metal liner is not present, a clay tile liner must be present, or
the chimney must be lined (Fix 4).
Use a flashlight and small mirror at the cleanout or vent connec-
tor to inspect the clay tile liner. If any of the following problems
are present:
• Tile sections misaligned
• Tile sections missing
• Gaps between tile sections
• Signs of condensate drainage at the cleanout or vent
connectors
• M ortar protruding from between tile sections
• Use of sewer pipe or drainage pipe rather than an
approved fire clay tile reline the chimney (Fix 4).
Next, measure the size of the liner. It may be possible to do this
from the cleanout. The liner must be at least as large as the mini-
mum size established by the tables in National Fuel Gas Code
NFPA 54/ANSI Z223.1 - latest edition and in the National Standard
of Canada, CAN/ CSA B149.1 and CAN/ CSA B149.2 - latest editions
and amendments. If the liner is too small or too large, then the
chimney must be relined (Fix 4).
CHECK 6 - DILUTION AIR.
If gas-fired appliances are to be vented into a clay tile liner, a
source of dilution air is required.
Dilution air cannot be obtained through:
• Induced draft appliances
• Natural draft appliances with vent dampers
Sufficient dilution air can ordinarily be obtained through the draft
hood of a natural draft appliance only if the appliance’s vent
connector does not include a vent damper. If dilution air will not
be available, the chimney must be relined (Fix 4).
CHECK 7 - COM PLETE THE INSTALLATION.
If Checks 1 through 6 have been satisfactory, and the liner is an
acceptable size as determined by the tables in National Fuel Gas
Code NFPA 54/ANSI Z223.1 - latest edition and in the National
Standard of Canada, CAN/ CSA B149.1 and CAN/ CSA B149.2 - latest
editions and amendments, then the clay tile liner can probably be
used as a vent for the gas appliances. However, the installer must
keep in mind the following factors which may render the tile liner
unsuitable for use as a vent:
• Extremely cold weather
• Long vent connectors