Table of Contents
Advertisement
Check 1 - Proper chimney termination
A masonry chimney used as a vent for gas fired equipment
must extend at least three feet above the highest point where it
passes through the roof. It must extend at least two feet higher
than any portion of a building within a horizontal distance of
10 feet. In addition, the chimney must terminate at least 3 feet
above any forced air inlet located within 10 feet. The chimney
must extend at least five feet above the highest connected
equipment draft hood outlet or flue collar.
If the chimney does not meet these termination requirements,
but all other requirements in the checklist can be met, it may
be possible for a mason to extend the chimney. If this will not
be practical, see Fix 1.
10' or Less
2' Min.
Termination 10 Feet Or Less From Ridge, Wall or Parapet
More than 10'
NOTE: No Height
above parapet
required when distance
Wall or
from walls or parapet is
Parapet
more than 10 feet.
Ridge
Termination More Than 10 Feet From Ridge, Wall or Parapet
2' Min.
3' Min.
Wall or
Parapet
10' or Less
2' Min.
3' Min.
3' Min.
Chimney
More than 10'
Height above any
roof surface within
10 feet horizontally.
10'
2" Min.
3' Min.
Chimney
Figure 8
Check 2 - Any solid or liquid fuel appliances
vented into this chimney channel
Solid fuel appliances include fireplaces, wood stoves, coal
furnaces, and incinerators.
Liquid fuel appliances include oil furnaces, oil-fired boilers and
oil-fired water heaters.
Appliances which burn propane (sometimes referred to as LP
(liquefied petroleum)) gas are considered gas-fired appliances.
Check 3 - Chimney Crown Condition.
Damage from condensate usually shows up first in the crown.
If any of the following trouble signs are present, the condition
of the crown is not satisfactory:
a) Crown leaning
b) Bricks missing
c) Mortar missing
d) Tile liner cracked
e) No tile liner
f) Salt staining at mortar joints. (White stains, and mortar
becomes sandy and/or erodes.)
For problems a, b, or c, see Fix 3. If problems d, e, or f are
present, see Fix 4. IMPORTANT: It may be necessary to follow
both Fix 3 and Fix 4.
Check 4 - Debris in Cleanout
A cleanout (dropleg) must be present such that the upper edge
of the cleanout cover is at least 12 inches below the lower
edge of the lowest chimney inlet opening.
A chimney without a cleanout could become partially blocked
by debris. If no cleanout is present, the chimney must be
relined (Fix 4). Remove the cleanout cover, and examine
the cleanout for debris. If significant amounts of any of the
following are found:
•
Fuel oil residue
•
Bricks
•
Mortar or sand
•
Pieces of the tile liner
•
Rusted pieces of the metallic liner - reline the chimney
(Fix 4).
Check 5 - Liner Condition.
If a metal liner is present, it must be checked. It cannot be
assumed that all existing metal liners are correctly installed
and in good condition.
Remove the lowest existing vent connector, and examine
the inside of the elbow or tee at the base of the liner. A small
amount of soot may be considered acceptable, provided the
installer vacuums it away. If rusted pieces of the liner have
collected here, the metal liner must be removed and replaced
(Fix 4).
Next, gently tap the inside of the liner with a Phillips screw-
driver. If the screwdriver perforates the liner, or if the tapping
does not sound like metal hitting metal, the liner must be
removed and replaced (Fix 4).
12
Advertisement
Table of Contents
Troubleshooting
