7
(A) - For Factory Built Fireplaces Free Opening Area of Chimney
Damper For Venting Combustion Products From Decorative Appliances
For Installation In Solid Fuel Burning Fireplaces
Appliance Input Rate (kBTU/hr)
40
50
60
70
80
90
Chimney
Minimum Opening** (sq. in.)
Max.
Height* (ft)
input***
10
22.1
28.3
35.3
44.2
__
__
77.6
15
17.3
21.2
26.4
32.2
28.5
45.4
98.2
20
14.5
18.1
22.1
26.4
31.2
37.4
114.2
25
12.6
15.9
18.1
22.9
27.3
31.2
121.0
30
11.3
14.5
17.3
20.4
24.6
28.3
130.1
35
10.8
13.2
15.9
18.9
22.1
25.5
141.2
40
10.2
12.6
15.2
18.1
20.4
23.8
158.5
(B) - For Masonry Built Fireplaces Free Opening Area of Chimney
Damper For Venting Combustion Products From Decorative Appliances
For Installation In Solid Fuel Burning Fireplaces
Warning:
Check the fireplace for proper venting,
use a match or smoke pen, if any spillage is noted then
the Damper shall be opened until no spillage occurs. If a
proper draft can not be obtained, contact your dealer for
assistance.
*
Height is from hearth to top of chimney and the minimum height is 10 feet.
**
Chart shows minimum opening (sq. in.) for the given height and input rate.
***
Column marked “Max. Input” corresponds to the maximum allowable input rate (kBTU/hr) for the given height.
Appliance Input Rate (kBTU/hr)
40
50
60
70
80
90
Chimney
Minimum Opening** (sq. in.)
Height* (ft)
6
33.8
41.7
49.2
56.6
64.0
71.4
8
31.2
38.7
45.5
52.4
59.7
66.9
10
28.7
35.2
41.7
48.5
54.3
60.2
15
26.1
32.0
37.7
43.2
48.8
54.1
20
23.7
28.8
34.4
39.8
44.4
49.1
30
21.6
26.5
31.2
35.9
40.3
44.5
*
Height is from hearth to top of chimney and the minimum height is 6 feet.
**
Chart shows minimum opening (sq. in.) for the given height and input
rate.
