36
Exchanger Length
Fixed or High-Fire
Gas Input BTU/h
Expansion Length
Feet
Meters
Inches
Millimeters
20
6.1
40,000
1
25.4
20
6.1
50,000
1 1/4
31.8
20
6.1
60,000
1 1/2
38.1
20
6.1
65,000
1 5/8
41.275
20
6.1
75,000
1 3/4
44.5
30
9.2
50,000
1 1/4
50.8
30
9.2
60,000
1 1/2
38.1
30
9.2
65,000
1 5/8
41.275
30
9.2
100,000
1 7/8
47.6
30
9.2
125,000
2
50.8
40
12.2
65,000
1 5/8
41.275
40
12.2
75,000
1 3/4
44.5
40
12.2
100,000
1 7/8
47.6
40
12.2
125,000
2
50.8
40
12.2
150,000
2 1/2
63.5
40
12.2
175,000
2 3/4
69.9
50
15.3
100,000
1 7/8
47.6
50
15.3
125,000
2
50.8
50
15.3
150,000
2 1/2
63.5
50
15.3
175,000
2 3/4
69.9
50
15.3
200,000
2 3/4
69.9
60
18.3
125,000
2
50.8
60
18.3
150,000
2 1/2
63.5
60
18.3
175,000
2 3/4
69.9
60
18.3
200,000
2 3/4
69.9
70
21.4
175,000
2 3/4
69.9
70
21.4
200,000
2 3/4
69.9
Allowances for Expansion
Allowances must be made for the system to expand as detailed in the Heater Expansion Chart below.
The supplied Type 1 hose gas connector is recommended. If, however, local codes require rigid piping to
the heater, a swing joint can be used.
Chart 3.9 •
Heater Expansion Chart
Exchanger length and gas input will determine overall expansion. Heaters in a typical installation will
expand towards both the burner and vent ends. Review for proper flexible gas connection.
3.0
Installation
•
Allowances for Expansion
DX2
Series