BED ROCK BURNER INSTALLATION & OPERATION MANUAL
GRANDCANYONGASLOGS.COM - 06_2021
GENERAL INSTRUCTIONS
6
Damper Stop Installation
The damper must be permanently locked in position to prevent full
closure and to provide a minimum flue opening. Various methods
for locking the damper may be used but may be restricted from
region to region and it is important to know the specifics that
apply to your area. For your convenience a damper stop is
provided with the appliance and may be used where not
prohibited by state or local codes.
Use the 3" adjustable bolt to adjust the damper to the correct opening, based on the enclosed chart.
Should the damper stop not fit, or provide the required permanent opening from the Minimum Damper Opening table, have the
damper cut to provide a minimum permanent opening or install an alternate stop.
Creosote, ashes and loose paint must be cleaned from the chimney flue and firebox by a qualified chimney cleaner, before installing
in a solid fuel burning appliance. Any outside air ducts and/or ash dumps in the fireplace shall be permanently closed at time of
appliance installation.
If the damper stop (supplied) is not applicable the damper may be fixed open by the following method:
• Drill a hole in either end of the damper.
• Using a bolt of sufficient length and adjustment, with 2 nuts, secure to damper through the hole.
• Adjust to correct opening.
Appliance must be installed only in a solid-fuel burning fireplace with a working flue and constructed of non-combustible material.
Appliance Input Rate (kBTU/hr)
Chimney
20
30
40
50
60
70
80
90
100
110
120
Maximum
Height (ft)
(Minimum opening in2)
Input
10
11.3
16.6
22.11
28.3
35.3
44.2
-
-
-
-
-
77.6
15
8.6
12.6
17.3
21.2
26.4
32.2
38.5
45.4
-
-
-
98.2
20
7.5
10.8
14.5
18.1
22.1
26.4
31.2
37.4
43
-
-
114.2
25
6.6
9.6
12.6
15.9
18.1
22.9
27.3
31.2
36.3
43
50.3
121
30
6.2
9.1
11.3
14.5
17.3
20.4
24.6
28.3
33.2
37.4
44.2
130.1
35
5.7
8
10.8
13.2
15.9
18.9
22.1
25.5
30.2
34.2
39.6
141.2
40
5.6
7.5
10.2
12.6
15.2
18.1
20.4
23.8
27.3
31.2
35.3
158.5
Height is from hearth to top of chimney and the minimum height is 10 feet (see Figure 3, Factory-built fireplace).
Chart shows some minimum opening (in2) for the given height and input rate.
Column marked “Maximum input” corresponds to the maximum allowable input rate (kBTU/hr) for the given height
Free opening area of chimney damper for venting combustion products (factory-built fireplaces)
Free opening area of chimney damper for venting combustion products (masonry-built fireplaces)
Appliance Input Rate (kBTU/hr)
Chimney
20
30
40
50
60
70
80
90
100
110
120
Height (ft)
(Minimum opening in2)
6
17.6
25.7
33.8
41.7
49.2
56.6
64
71.4
78.8
86.2
93.5
8
16.5
23.7
31.2
38.7
45.5
52.4
59.7
66.9
74.1
81.3
88.6
10
15.1
21.7
28.7
35.2
41.7
48.2
54.3
60.2
66.1
72
77.9
15
14.1
19.9
26.1
32
37.7
43.2
48.8
54.1
59.4
64.6
69.9
20
12.9
18.5
23.7
28.8
34.3
39.8
44.4
49.1
53.8
58.4
63
30
12.2
16.9
21.6
26.5
31.2
35.9
40.3
44.5
48.6
52.7
56.6
Height is from hearth to top of chimney and the minimum height is 6 feet (see Figure 3, Factory-built fireplace).
Chart shows some minimum opening (in2) for the given height and input rate
Venting Requirements
